RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: Two vehicles each 900 m long are running in opposite directions on parallel paths. Their speeds are 50 km/hr and 30 km/hr respectively. Find the time taken by the slower train to pass the driver of the faster one?
A.77 sec
B.66 sec
C.48 sec
D.81 sec
Answer: D.81 sec
Explanation: Relative speed = 50 + 30 =80 km/hr.
80 * 5/18 = 200/9 m/sec.
Distance covered = 900 + 900 = 180 m.
Required time = 1800 * 9/200 = 81 sec.
Answer: D
Question: If John invested $ 1 at 5 percent interest compounded annually, the total value of the investment, in dollars, at the end of 5 years would be
A.(1.5)^4
B.4(1.5)
C.(1.05)^5
D.1 + (0.05)^4
Answer: C.(1.05)^5
Explanation: f John invested $ 1 at 5 percent interest compounded annually, the total value of the investment, in dollars, at the end of 5 years would be
1(1.05)^5
1.05^5
C. (1.05)^5
Question: If a fisherman rows upstream at 7kmph, and downstream at 10kmph, what is the speed of the stream?
A.1.7 kmph
B.1.5 kmph
C.2.5 kmph
D.1.9 kmph
Answer: B.1.5 kmph
Explanation: Sol.
Speed of stream = 1/2(10 -7) kmph = 1.5 kmph.
Answer B
Question: The youngest of 4 children has siblings who are 4, 5, and 7 years older than she is. If the average (arithmetic mean) age of the 4 siblings is 21, what is the age of the youngest sibling?
A.14
B.15
C.16
D.17
Answer: D.17
Explanation: x + (x+4) + (x+5) + (x+7) = 84
4x + 16 = 84
4x = 68
x = 17
The answer is D.
Question: The edge of a cube is 4a cm. Find its surface?
A.24a8
B.24a4
C.96a2
D.24a2
Answer: C.96a2
Explanation: 6a2 = 6 * 4a * 4a = 96a2
Answer:C
Question: A, B and C can do a piece of work in 24, 30 and 40 days respectively. They start the work together but C leaves 4 days before the completion of the work. In how many days is the work done?
A.15 days
B.14 days
C.13 days
D.11 days
Answer: D.11 days
Explanation: Explanation:
x/24 + x/30 + x/40 = 1
x = 11 days
ANSWER IS D
Question: Find the principle on a certain sum of money at 5% per annum for 2 2/5 years if the amount being Rs.1120?
A.1000
B.1288
C.2778
D.2682
Answer: A.1000
Explanation: 1120 = P [1 + (5*12/5)/100]
P= 1000
Answer: A
Question: The ratio of pens to pencils is 5 to 6. There are 4 more pencils than pens. How many pencils are there?
A.12
B.16
C.20
D.24
Answer: D.24
Explanation: Let the number of pens be 5x and the number of pencils be 6x.
6x - 5x = 4
x = 4
The number of pencils is 24.
The answer is D.
Question: Two dice are tossed. The probability that the total score is a prime number is
A.3/8
B.4/9
C.5/12
D.4/7
Answer: C.5/12
Explanation: n(S)=36
E= {(1,1),(1,2), (1,4),….(6,5)}
n(E)=15
P(E)=15/36
=5/12
Ans: C
Question: Reena took a loan of Rs. 1200 with simple interest for as many years as the rate of the interest. If she paid Rs. 432 as interest at the end of the period,what was the rate of interest ?
A.3.6
B.6
C.18
D.Cannot be determined
Answer: B.6
Explanation: Solution
Let rate = R% and time = R years.Then,
(1200xRxR/100)= 432 = 12R2= 432 = R2=36 =R = 6
Answer B
Question: A and B together have Sterling 1240. If 4/15 of A's amount is equal to 2/5 of B's amount, how much amount does B have?
A.Sterling 496
B.Sterling 484
C.Sterling 550
D.Sterling 664
Answer: A.Sterling 496
Explanation: Explanation: 4/15A = 2/5B
A = (2/5 x 15/4)B
A = 3/2 B
A/B = 3/2
A : B = 3 : 2.
B's share = Sterling (1240 x 2/5) = Sterling 496.
Answer: Option A
Question: If the sides of a triangle are 39 cm, 36 cm and 15 cm, what is its area?
A.120 cm2
B.765 cm2
C.216 cm2
D.270 cm2
Answer: D.270 cm2
Explanation: The triangle with sides 39 cm, 36 cm and 15 cm is right angled, where the hypotenuse is 39 cm.
Area of the triangle
= 1/2 * 36 * 15
= 270 cm2
Answer: D
Question: What is the average of xx, 2x2x, and 66?
A.2x+2
B.x+2x
C.x+2x+2
D.x+2
Answer: C.x+2x+2
Explanation: By the definition of an average, we get:
x+2x+63=3x+63x+2x+63=3x+63
=3(x+2)3=x+2.=3(x+2)3=x+2.
Hence, the answer is x+2x+2 or Option C
Question: A 6% stock yields 8% . The market value of the stock is?
A.Rs.11
B.Rs.75
C.Rs.17
D.Rs.16
Answer: B.Rs.75
Explanation: For an income of Rs. 8, investment = Rs. 100.
For an income of Rs 6, investment =Rs. \inline \left ( \frac{100}{8} \times 6\right ) = Rs. 75
Market value of Rs. 100 stock = Rs. 75.
Answer: B
Question: Two trains of length 100 m and 200 m are 100 m apart. They start moving towards each other on parallel tracks, at speeds 54 kmph and 72 kmph. After how much time will the trains meet?
A.20/7
B.20/5
C.20/9
D.20/5
Answer: A.20/7
Explanation: They are moving in opposite directions, relative speed is equal to the sum of their speeds.
Relative speed = (54 + 72)*5/18 = 7*5 = 35 mps.
The time required = d/s = 100/35 = 20/7 sec.
Answer:A
Question: It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the car is?
A.3:4
B.7:6
C.1:4
D.5:4
Answer: A.3:4
Explanation: A
3:4
Let the speed of the train be x km/hr and that of the car be y km/hr.
Then, 120/x + 480/y = 8 or 1/x + 4/y = 1/15 --- (i)
And, 200/x + 400/y = 25/3 or 1/x + 2/y = 1/24 --- (ii)
Solving (i) and (ii), we get x = 60 and y = 80
Ratio of speeds = 60:80 = 3:4
Question: The bus that travels from St. Louis to Chicago and back comes to St. Louis every 5 hours while the bus that travels from St. Louis to Springfield and back comes to St. Louis every 2 hours. If at 12:00 o'clock both bused arrived at St. Louis, at what time will they meet in St. Louis again?
A.16:00.
B.18:00
C.20:00
D.22:00.
Answer: D.22:00.
Explanation: Time taken by bus to travel from St. Louis to Chicago and back comes to St. Louis = 5 hours
Time taken by bus to travel from St. Louis to Springfield and back comes to St. Louis = 2 hours
Time taken by both buses to meet again in St. Louis will be LCM of 5 and 2 = 10
If the buses start at 12:00 o'clock from St. Louis , they will meet again in St. Louis at 22:00 hours
Answer D
Question: If (4x + 3)(x - 2) = 4x^2 + x, what is a possible value of x?
A. 5
B. -6
C. -1
D. 1
Answer: C. -1
Explanation: Rearranging the given expression:
(4x + 3)(x - 2) = 4x^2 + x
i.e. 4x^2 - 5x - 6 = 4x^2 + x
i.e. -6x = 6
i.e. x = 6/-6 = -1
Answer: Option C
Had it been a difficult expression to solve further, then we could have used options to check which on esatisfies the expression after solving it as further as possible
Question: If 2 dice are rolled, what is the probability of the total score being a even number?
A.1/4
B.1/3
C.5/12
D.1/2
Answer: D.1/2
Explanation: Using the rules of probability, the likelihood of rolling a even number would be 1/2, as half the numbers from 1-12 are even numbers. Answer: D
Question: A bag contains a certain number of 50 paise coins, 20 paise coins and 10 paise coins inthe ratio 2:3:4. If the total value of all the coins in the bag is Rs.400, find the number of coins of each kind?
A.800
B.277
C.266
D.288
Answer: A.800
Explanation: 50*2k + 20*3k + 10*4k = 40000
200k = 40000 => k = 200
50p coins = 2k = 2*200 = 400
20p coins = 3k = 3*200 = 600
10p coins = 4k = 4*200 = 800
Answer: A
Question: Three candidates contested an election and received 1136, 7636 and 11628 votes respectively. What percentage of the total votes did the winning candidate get?
A.57%
B.63%
C.73%
D.90%
Answer: A.57%
Explanation: Total number of votes polled = (1136 + 7636 + 11628) = 20400.
Required percentage =(11628/20400	)x 100% = 57%.
Answer:A
Question: An empty pool being filled with water at a constant rate takes 7 hours to fill to 3/5 of its capacity. How much more time will it take to finish filling the pool?
A.5 hr 30 min
B.5 hr 20 min
C.4 hr 40 min
D.3 hr 12 min
Answer: C.4 hr 40 min
Explanation: (3/5) of a pool/ 7 hours = 3/35 (the rate)
(3 pools/35 hours) = (2/5* pool)/ x hours
Cross multiply 3x = (2/5) 35
x = 4 2/3
2/3 of an hour = 40 minutes
C
Question: In a village of 100 households, 75 have at least one DVD player, 85 have at least one cell phone, and 70 have at least one MP3 player. If x and y are respectively the greatest and lowest possible number of households that have all three of these devices, x – y is:
A.65
B.55
C.40
D.35
Answer: C.40
Explanation: Am I missing something here??? it seems straightforward......
The obvious maximum that have all 3 is 70, because you are limited by the SMALLEST number.
The minimum is simply the sum of the max of each people who DONT have the product, so:
100-85 = 15 don't have Cell
100-75 = 25 don't have DVD
and 100-70 = 30 don't have MP3
SO a total of 15+25+30 = 70 combined who might NOT have SOME combination of the 3 products. So subtract that from 100, to give you the minimum of the people who COULD have all 3 and you get 100-70 = 30.
70-30 = 40
C
Question: The average age of husband, wife and their child 3 years ago was 28 years and that of wife and the child 5 years ago was 20 years. The present age of the husband is
A.22
B.40
C.33
D.21
Answer: C.33
Explanation: Explanation:
Sum of the present ages of husband, wife and child = (28 x 3 + 3 x 3) years = 93 years.
Sum of the present ages of wife and child (20 x 2 + 5 x 2) years = 50 years.
Husband's present age = (93 - 50) years = 33 years.
Answer: C
Question: What amount does Kiran get if he invests Rs. 18000 at 15% p.a. simple interest for four years?
A.28800
B.24800
C.24400
D.20000
Answer: A.28800
Explanation: Simple interest = (18000 * 4 * 15)/100 = Rs. 10800
Amount = P + I = 18000 + 10800 = Rs. 28800
ANSWER A
Question: A electronics shop has a sale of Rs. 16000, Rs. 25000, Rs. 65000 for 3 consecutive months. How much sale must he have in the fourth month so that he gets an average sale of Rs. 40000?
A.s. 499110
B.s. 165000
C.s. 114000
D.s. 250000
Answer: C.s. 114000
Explanation: Total sale for 3 months = Rs. (16000 + 25000 + 65000) = Rs. 106000.
Required sale = Rs. [ (55000 x 4) - 106000]
= Rs. 220000 - 106000)
= Rs. 114000.
Option C
Question: A person travels from P to Q a speed of 40 km/hr and returns by increasing his speed by 50%. What is his average speed for both the trips?
A.27 km/hr
B.28 km/hr
C.48 km/hr
D.19 km/hr
Answer: C.48 km/hr
Explanation: Speed on return trip = 150% of 40
= 60 km/hr.
Average speed = (2 * 40 * 60)/(40 + 60)
= 48 km/hr.
Answer:C
Question: A 9-meter long wire is cut into two pieces. If the longer piece is then used to form a perimeter of a square, what is the probability that the area of the square will be more than 4 if the original wire was cut at an arbitrary point?
A.1/5
B.2/7
C.2/9
D.3/10
Answer: C.2/9
Explanation: The longer wire will form a square with an area more than 4 if the wire is cut at a point within one meter of either end. The probability of this is 2/9.
The answer is C.
Question: A 1500 m long train crosses a tree in 120 sec, how much time will it take to pass a platform 500m long?
A.288
B.160
C.188
D.188
Answer: B.160
Explanation: L = S*T
S= 1500/120
S= 12.5m/Sec.
Total length (D)= 2000 m
T = D/S
T = 2000/12.5
T = 160 Sec
Answer:B
Question: How many seconds will a 600 meter long train moving with a speed of 63 km/hr take to cross a man walking with a speed of 3 km/hr in the direction of the train ?
A.48
B.36
C.26
D.11
Answer: B.36
Explanation: Explanation:
Here distance d = 600 mts
speed s = 63 - 3 = 60 kmph = 60 x 5/18 m/s
time t = = 36 sec.
Answer: B
Question: A man spends Rs. 1600 per month on an average for the first three months, Rs 1550 for next four months and Rs. 1800 per month for the last five months and saves Rs . 5200 a year. What is his average monthly income?
A.Rs. 2000
B.Rs. 2010
C.Rs. 2100
D.Rs. 2200
Answer: C.Rs. 2100
Explanation: Total expenditure for the first 3 months = 3 × 1600 = 4800
Total expenditure for 4 months = 4 × 1550 = 6200
Total expenditure for 5 months = 5 × 1800 = 9000
Total expenditure and saving (which is income for one year)
= 4800 + 6200 + 9000 + 5200 = Rs. 25200
So, Average monthly income = 25200/12 = Rs. 2100
C
Question: 10 camels cost as much as 24 horses, 16 horses cost as much as 4 oxen and 6 oxen as much as 4 elephants. If the cost of 10 elephants is Rs.110000, find the cost of a camel?
A.s.9800
B.s.3800
C.s.9800
D.s.4400
Answer: D.s.4400
Explanation: Cost of the camel = P
10 camels = 24 horses
16 horses = 4 oxen
6 oxen = 4 elephants
10 elephants = Rs.110000
P = Rs.[(24 * 4 * 4 * 110000)/(10 * 16 * 6 * 10)]
P = Rs.(42240000/9600) => P = Rs.4400
Answer:D
Question: The product of all the prime numbers less than 10 is closest to which of the following powers of 10?
A.10^9
B.10^2
C.10^7
D.10^6
Answer: B.10^2
Explanation: Quickly approximate
2, 3, 5, 7, = 210 =2.1x10^2
B
Question: The difference between the costs of two brands is 20 Rs. Ten years ago, the costlier one was thrice as costly as the cheaper one. The present price of the costlier brand is
A.30
B.20
C.10
D.40
Answer: A.30
Explanation: Let their costs of x Rs and (x + 20) Rs respectively.
Then, (x + 20) - 10 = 3(x - 10)
⇔ x +10= 3x - 30
⇔ 2x = 40
∴ Present cost of the costlier person = (20 + 10)
= 30Rs.
Answer :Rs.30
Question: Water consists of hydrogen and oxygen, and the approximate ratio, by mass, of hydrogen to oxygen is 2:16. Approximately how many grams of oxygen are there in 90 grams of water?
A. 16
B. 90
C. 112
D. 128
Answer: B. 90
Explanation: Solution:
We are given that the ratio of hydrogen to oxygen in water, by mass, is 2 : 16. Using our ratio multiplier we can re-write this as 2x : 16x. We can now use these expressions to determine how much oxygen is in 90 grams of water.
2x + 16x = 90
18x = 90
x = 5
Since x is 5, we know that there are 16 x 5 = 80 grams of oxygen in 90 grams of water.
Answer B.
Question: How many three letter words are formed using the letters of the word TIME?
A.27
B.20
C.28
D.24
Answer: D.24
Explanation: The number of letters in the given word is four.
The number of three letter words that can be formed using these four letters is ⁴P₃
= 4 * 3 * 2 = 24.
Answer: D
Question: How many different four letter words can be formed (the words need not be meaningful) using the letters of the word MEDITERRANEAN such that the first letter is E and the last letter is R?
A.59
B.11! / (2!*2!*2!)
C.56
D.23
Answer: A.59
Explanation: Explanatory Answer
Select 2 letters and rearrange them
MEDITERRANEAN is 13-letter word.
We have to make 4 letter words that start with an 'E' and end with 'R'.
Therefore, we have to find two more letters from the remaining 11 letters.
Of the 11 letters, there are 2 Ns, 2Es and 2As and one each of the remaining 5 letters.
The second and third positions can either have two different letters or can have both as same letters.
Case 1: When the two letters are different
One has to choose two different letters from the 8 available different choices.
This can be done in 8 * 7 = 56 ways.
Case 2: When the two letters are same
There are 3 options - the two letters can be Ns or Es or As. Therefore, 3 ways.
Total number of posssibilities = 56 + 3 = 59
Choice A
Question: Sachin's age after 15 years will be 5 times his age 5 years back. Find out the present age of Sachin?
A.5
B.10
C.8
D.9
Answer: B.10
Explanation: Let present age of Sachin =x. Then,
(x+15)=5(x−5)⇒4x=40⇒x=10
Answer is B.
Question: Find the quotient: 0.0204 / 17
A.0.012
B.0.12
C.0.0012
D.0.00012
Answer: C.0.0012
Explanation: 204 / 17 = 12. Dividend contains 4 places of decimal.
0.2040 / 17 = 0.0012.
Answer is C.
Question: A fair coin is tossed 5 times. What is the probability of getting at least three heads on consecutive tosses?
.
A.2/16
B.1/4
C.7/24
D.5/16
Answer: B.1/4
Explanation: Brunnel explained it in detail. I would just count the number of possibilities and divide it by 2^n
HHHHH
HHHTT
HHHHT
THHHT
TTHHH
HHHTH
THHHH
HTHHH
8/(2)^5 ==> 8/32 ==> 1/4
Answer: B
Question: If the operation Ø is defined for all positive integers x and w by x Ø w = (2^x)/(2^w) then (4 Ø 2) Ø 3 = ?
A.2
B.4
C.8
D.16
Answer: A.2
Explanation: 4 Ø 2 = 2^4/2^2 = 4
4 Ø 3 = 2^4/2^3 = 2
The answer is A.
Question: A person saved $10 in buying an item on sale. If he spent $600 for the item, approximately how much percent he saved in the transaction?
A.8%
B.1.6%
C.2%
D.5%
Answer: B.1.6%
Explanation: Actual price = 600+10 = $610
Saving = 10/610 * 100 = 100/61 = 1.6% approximately
Answer is B
Question: A right angled cone has its height 'h'. The cone is being cut parallel to its base at h/5 distance from its vertex. What will be the ratio of the cone and the cutting portion
A.1:124
B.1:125
C.1:25
D.1:26
Answer: A.1:124
Explanation: let radius of smaller cone=R
radius of bigger cone=r
height of smaller cone=h/5
height of bigger cone=h
volume of smaller cone=1/3*pi*R^2*h
volume of reamaining portion=volume of bigger cone - volume of smaller cone
i.e 1/3*pi*r^2h-1/3*pi*R^2(h/5)
from the similarity of triangle
r/R=5:1
equating value
we get 1:124
ANSWER:A
Question: 6 x 0.6 x 0.06 x 0.006 x 60 = ?
A.77.76
B.7.776
C.0.7776
D.0.07776
Answer: D.0.07776
Explanation: Explanation:
? = 6 x 6/10 x 6/100 x 6/1000 x 60 = 77760/1000000
= 7776/100000 = 0.07776
Answer: Option D
Question: A shopkeeper sells some articles at the profit of 25% on the original price. What is the exact amount of profit? To find the answer, which of the following information given in Statements I and II is/are necessary?
I. Sale price of the article
II. Number of articles sold
A.Only I is necessary
B.Only II is necessary
C.Either I or II is necessary
D.Both I and II are necessary
Answer: D.Both I and II are necessary
Explanation: EXPLANATION
Gain = 25% of C.P.
In order to find gain, we must know the sale price of each article and the number of articles sold.
answer is (D).
Question: If the average (arithmetic mean) of a and b is 110, and the average of b and c is 160, what is the value of a − c?
A.−220
B.−100
C.100
D.135
Answer: B.−100
Explanation: (a + b)/ 2 =110 ===> a + b = 220
(b + c)/2 = 160 ===> b + c = 320
(a + b) - (b + c) = 220 - 320 ===> a + b - b - c = - 100 ===> a - c = - 100
Answer: B
Question: If the total distance of a journey is 120 km .If one goes by 60 kmph and comes back at 40kmph what is the average speed during the journey?
A.38km/hr
B.58km/hr
C.68km/hr
D.48km/hr
Answer: D.48km/hr
Explanation: total distance=2*120
total time=120/60+120/40=5 hours
avg=120*2/5=48km/hr
ANSWER:D
Question: Raj invested an amount of Rs.17400 for two years. Find the rate of compound interest that will fetch him an amount of Rs.1783.50 at the end of two years?
A.7
B.6
C.9
D.5
Answer: D.5
Explanation: Let the rate of interest be R% p.a.
17400[1 + R/100]2 = 17400 + 1783.50
[1 + R/100]2 = (17400 + 1783.50)/17400
= 1 + 1025/10000 = 1 + 41/400
= 441/400 = [21/20]2
[1 + R/100] = 21/20
R/100 = 1/20
Therefore R = 5
Answer:D
Question: For any integer k greater than 1, the symbol k* denotes the product of all integers between 1 and k, inclusive. If k* is a multiple of 315 what is the least possible value of k?
A.5
B.7
C.9
D.11
Answer: B.7
Explanation: 315 = 3*3*5*7
Thus k must include numbers at least up to the number 7.
The answer is B.
Question: A sum of Rs. 12500 amounts to Rs. 15000 in 4 years at the rate of simple interest. What is the rate of interest?
A.4%
B.5%
C.6%
D.8%
Answer: B.5%
Explanation: S.I. = (15000 - 12500) = Rs. 2500/-
Rate = (100 * 2500) / (12500 * 4) = 5%
ANSWER:B
Question: In how many ways can 9 people, A, B, C, D, E, F, G, H, I be seated in a row such that C and D are not seated next to each other as well as A and B are not seated next to each other?
A.3841258
B.39600
C.576822
D.362784
Answer: D.362784
Explanation: Number of total arrangements = 9!
Restriction 1= ABCD not next to each other --> let say AB and CD are considered as one unit, respectively
Restriction 2= AB is not the same as BA + CD is not the same as DC --> the number will increase by 2*2
Total number of arrangements - Number out of restrictions = Result
9! - (4!*2*2) = 362880 - (24*2*2) = 362784
Answer D
Question: A pharmaceutical company received $3 million in royalties on the first $25 million in sales of and then $9 million in royalties on the next $130 million in sales. By approximately what percentage did the ratio of royalties to sales decrease from the first $25 million in sales to the next $130 million in sales?
A.8%
B.15%
C.35%
D.42%
Answer: D.42%
Explanation: (9/130)/(3/25) = 15/26 = 57.7% it means that 9/130 represents only 57.7%. Therefore a decrease of 42%.
Answer D
Question: A windmill is taking advantage of strong air currents in order to produce electrical energy. On a typical day the wind speed is around 20 mph and in that speed the windmill produces 300 kw/h (kilowatts per hour). On a stormy day a windmill produces 20% more energy. How much kw/h can three windmills produce in two hours on a stormy day?
A.2880.
B.2160.
C.5780
D.5760
Answer: B.2160.
Explanation: Normal Day = 300 kw/h
Stormy Day = 300*1.2=360 kw/h
3 windmills for 2 hours on stormy day
360*3*2=2160
Answer: B
Question: A man is 24 years older than his son. In two years, his age will be twice the age of his son. The present age of his son is
A.20 years
B.21 years
C.22 years
D.24 years
Answer: C.22 years
Explanation: Explanation:
Let the son's present age be x years. Then, man's present age = (x + 24) years
=> (x + 24) + 2 = 2(x + 2)
=> x + 26 = 2x + 4
So, x = 22
Option C
Question: A CAN FINISH A WORK IN 12 DAYS AND B CAN DO THE SAME WORK IN15 DAYS. B WORKED FOR 10 DAYS AND LEFT THE JOB. IN HOW MANY DAYS, A ALONE CAN FINISH THE REMAINING WORK?
A.4
B.5 1/2
C.6
D.8
Answer: A.4
Explanation: B'S 10 DAY'S WORK=(1/15*10)=2/3 REMAINING WORK = (1-2/3)=1/3
NOW, 1/18 WORK IS DONE BY A IN 1 DAY
1/3 WORK IS DONE BY A IN (12*1/3)=4 DAYS.
CORRECT OPTION:A
Question: On a sum of money, simple interest for 2 years is Rs 660 and compound interest is Rs 696.30, the rate of interest being the same in both cases.
A.8%
B.9%
C.10%
D.11%
Answer: D.11%
Explanation: Explanation:
Difference between C.I and S.I for 2 years = 36.30
S.I. for one year = 330.
S.I. on Rs 330 for one year = 36.30
So R% = \frac{100*36.30}{330*1} = 11%
Option D
Question: In a group of 800 people, 1/5 play at least one instrument, 64 play two or more. What is the probability that one student play exactly one instrument?
A.3/25
B.3/125
C.C)2/25
D.3/25
Answer: A.3/25
Explanation: P(playing 2 or more instruments) = 64/800 = 2/25.
Then, the probability of playing exactly one instrument is given by:
P(playing 1 or more instruments) - P(playing 2 or more instruments) = 1/5 - 2/25 = 3/25.
Answer A.
Question: Dhoni can read m pages in 2 minutes. At this rate, how long will it take him to read n pages?
A.(2/m)*n
B.(3/m)*n
C.(4m)*n
D.(6/m)*n
Answer: A.(2/m)*n
Explanation: m page in 2 mins
i.e. 1 page in 2/m mins
i.e. n pages in (2/m)*n
Answer: option A
Question: If the perimeter of a rectangular garden is 600 m, its length when its breadth is 100 m is?
A.650 m
B.600 m
C.200 m
D.300 m
Answer: C.200 m
Explanation: Explanation:
2(l + 100) = 600 => l = 200 m
ANSWER IS C
Question: How many different pairs of positive integers (a, b) satisfy the equation 1/a+1/b=32/51 ?
A.6
B.3
C.2
D.1
Answer: C.2
Explanation: There is no certain way to solve 2 unknown with 1 equation. The best way is to look at the question and retrospect the most efficient way. In this question, a and b are only positive integers. So that is a big relief. Now, we can start with putting a=1,2,.. and so on till the time we are confident about one of the options.
So, we start with
a=1, we get b as -ve. out
a=2, we get b as 6. Yes (Now (a,b) = (2,6). We can directly see that (a,b)=(6,2) will also satisfy. So we have 2 possible solutions)
a=3, we get b as 3. Yes (Now we have 3 possible solutions)
a=4, we get b as fraction. Out
a=5, we get b again as some fraction. Out
a=6 already taken.
We have A,B options left. C,D,E are out.
A is 6. To have 6 as the answer, we will need one more pair like2,6and one more solution where a=b.
When a=b, we have only 1 solution = 2. So, one more solution, where a=b is not possible.
So, answer will be C.
Question: If x is negative, which of the following must be positive ?
I. x^2
II. (-1) x
III. 1/x
A.I only
B.I and II only
C.I and III only
D.II and III only
Answer: B.I and II only
Explanation: x=-ve
I. x^2
will be positive
II. (-1) x
=-ve*-ve= +ve
will be positive
III. 1/x
=1/-ve =-ve
will be negative
Answer B
Question: The mean of 50 observations was 36. It was found later that an observation 47 was wrongly taken as 23. The corrected new mean is
A.35.24
B.36.16
C.36.22
D.36.48
Answer: D.36.48
Explanation: Solution
Correct sum = (36x50+47-23)
= 1824.
âˆ´ Correct mean = 1824 / 50
= 36.48.
Answer D