RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: A man can row upstream at 5 kmph and downstream at 25kmph, and then find the speed of the man in still water?
A.15
B.77
C.30
D.88
Answer: A.15
Explanation: US = 5
DS = 25
M = (5 + 25)/2 = 15
Answer:A
Question: Anthony and Michael sit on the six member board of directors for company X. If the board is to be split up into 2 three-person subcommittees, what percent W of all the possible subcommittees that include Michael also include Anthony?
A. 20%
B. 30%
C. 40%
D. 50%
Answer: C. 40%
Explanation: The answer is C. Let's look at a committee where Mike belongs (he's person # 1) on that committee. When we choose person #2, there is a 1/5 probability that it's going to be Anthony (then it doesn't matter who the third person is), and 4/5 probability that it's going to be someone else (then person #3 is going to be Anthony with probability 1/4). Total probability W= 1/5+4/5*1/4 = 2/5.C
Question: The height of the wall is 6 times its width and length of the wall is 8 times its height .if the volume of the wall be 36000 cu.m.its width is
A.4m
B.5m
C.6m
D.7m
Answer: B.5m
Explanation: Explanation:
Let width = x
Then, height=6x and length=48x
48x Ã— 6x Ã— x = 36000
x = 5
Answer: B
Question: A cricket bat is sold for $900, making a profit of $150. The profit percentage would be
A.24%
B.20%
C.30%
D.36%
Answer: B.20%
Explanation: 150/(900 - 150) = 150/750 = 0.2 = 20%.
Answer: B
Question: The average weight of a group of boys is 20 kg. After a boy of weight 32 kg joins the group, the average weight of the group goes up by 1 kg. Find the number of boys in the group originally ?
A.12
B.11
C.18
D.24
Answer: B.11
Explanation: Let the number off boys in the group originally be x.
Total weight of the boys = 20x
After the boy weighing 32 kg joins the group, total weight of boys = 20x + 32
So 20x + 32 = 21(x + 1) = > x = 11.
ANSWER:B
Question: A shopkeeper buys mangoes at the rate of 5 a rupee and sells them at 3 a rupee. Find his net profit or loss percent?
A.33 4/3 %
B.33 1/7 %
C.40 %
D.32 1/3 %
Answer: C.40 %
Explanation: The total number of mangoes bought by the shopkeeper be 15.
If he buys 5 a rupee, his CP = 3
He selling at 3 a rupee, his SP = 5
Profit = SP - CP = 5 - 3 = 2
Profit Percent = 2/5 * 100 = 40 %
Answer:C
Question: The cost of10 kgs. of sugar is Rs.300. What is the cost of .200kgs. of sugar?
A.Rs.3
B.Rs.50
C.Rs.5
D.Rs.6
Answer: D.Rs.6
Explanation: Explanation:
The cost of .200 kgs. of sugar = 300x .200/10 = Rs.6
Answer: Option D
Question: A does a work in 10 days and B does the same work in 15 days. In how many days they together will do the same work ?
A.5 days
B.6 days
C.7 days
D.8 days
Answer: B.6 days
Explanation: Explanation:
Firstly we will find 1 day work of both A and B, then by adding we can get collective days for them,
So,
A's 1 day work = 1/10
B's 1 day work = 1/15
(A+B)'s 1 day work =
(1/10+1/15)=(3+2/30)=1/6
So together they can complete work in 6 days.
Option B
Question: A man can hit the target once in four shots. If he fires two shots in succession, what is the probability that he will hit the target?
A.7/16
B.1/256
C.81/256
D.175/256
Answer: A.7/16
Explanation: In two shots he can hit once,all hit
the probability of hitting the target is p(1hit out of 2+ p(All hit)
it is total probability-probability of not hitting the target
=>1-(3/4*3/4)
=>7/16
ANSWER:A
Question: 12 times a positive integer is more than its square by 36, then the positive integer is
A.6
B.10
C.11
D.12
Answer: A.6
Explanation: Explanation:
Let the number be x. Then,
12x = x2 + 36
=> x2 - 12x + 36 = 0
=>(x - 6)(x - 6) = 0
=> x = 6
Answer: A
Question: pipes P and Q would fill a cistern 18 and 24 minutes respectively. Both pipes being opened, find when the first pipe must be turned off so that the cistern may be just filled in 12 minutes?
A.2
B.9
C.8
D.7
Answer: B.9
Explanation: x/18 + 12/24 = 1
x = 9
Answer: B
Question: Machines P and Q are two different machines that cover jars in machine shop. When Machine P works alone, it covers 5 jars in m hours. When Machines P and Q work simultaneously at their respective rates, they cover 5 jars in n hours. In terms of m and n, how many hours does it take Machine Q, working alone at its constant rate, to cover 5 jars?
A.m
B.n
C.m+n
D.5n/25-mn
Answer: D.5n/25-mn
Explanation: working rate p = 5/m ; working rate pq =( 1/p +1/q)* n =5 or mn/5 +n/q =5 0r n/q = 5-mn/5 = 25-mn/5
q = 5n/25-mn
D
Question: Free notebooks were distributed equally among children of a class. The number of notebooks each child got was one-eighth of the number of children. Had the number of children been half, each child would have got 16 notebooks. Total how many notebooks were distributed ?
A.412
B.512
C.312
D.112
Answer: B.512
Explanation: Let total number of children be x.
Then, (x) x 1/8x = (x/2)x 16
= x = 64.
Number of notebooks = 1/8 x2 = (1/8	x 64 x 64)	= 512.
Answer is B.
Question: A man sells two articles for Rs.2850 each and he gains 32% on the first and loses 18% on the next. Find his total gain or loss?
A.9%loss
B.2%loss
C.7%loss
D.6%loss
Answer: D.6%loss
Explanation: Explanation:
(32*18)/100
= 6%loss
Answer:D
Question: The perimeter of a square is 48 m. Find the area of the square.
A.161 mÂ².
B.144 mÂ².
C.166 mÂ².
D.169 mÂ².
Answer: B.144 mÂ².
Explanation: Perimeter of square = 48 m
But perimeter of square = 4 Ã— side
Therefore, 4 Ã— side = 48 m
Therefore, side= 48/4 m = 12m
Now, the area of the square = (side Ã— side)
Therefore, area of the square = 12 Ã— 12 mÂ² = 144 mÂ².
ANSWER : OPTION B
Question: Five bells first begin to toll together and then at intervals of 5, 10, 15, 20 and 25 seconds respectively. After what interval of time will they toll again together?
A.5 min
B.5.5 min
C.5.2 min
D.6.2 min
Answer: A.5 min
Explanation: LCM = 300/60 = 5 min
ANSWER:A
Question: As x increases from 131 to 132, which of the following increases?
I) x−1/x
II) 17−1/x
III) (17+x)/x
A.I only
B.II only
C.I,II only
D.II,III only
Answer: C.I,II only
Explanation: On Increasing the value of x from 131 to 132
I) x−1/x will increase as 1/x will be very small and x will increase by 1 unit
II) 17−1/x Will Increase as the value of 1/x will decrease thereby increasing the value of 17-(1/x)
III) (17+x)/x = (17/x)+1 will Decrease as 1/x will decrease thereby decreasing the value of (17/x)
Answer:C
Question: 16 men can complete a piece of work in 25 days. In how many days can 20 men complete that piece of work?
A.27
B.29
C.20
D.22
Answer: C.20
Explanation: 16 * 25 = 20 * x => x = 20 days
Answer:C
Question: Two cars start at the same time from opposite ends of a highway that is 333 miles long. One car is riding at 54 mph and the second car is riding at 57 mph. How long after they begin will they meet?
A.1
B.2
C.3
D.4
Answer: C.3
Explanation: As cars are moving in opposite directions their speeds will be added. So their relative speeds: 57+54 = 111 mph
Total distance to be covered = 333 miles.
Time taken would be: 333 miles/111 mph = 3 hours
C is the answer.
Question: You have a rock solid dark chocolate bar of size 2 x 8. You need to break it and get 1 x 1 pieces of that chocolate.
If you can break that bar only along its length or breadth, how many times will you have to break to get the 1 x 1 pieces?
A.12 times.
B.13 times.
C.14 times.
D.15 times.
Answer: D.15 times.
Explanation: Solution:
There is a simple logic to solve this question.
The size of the chocolate is 2 x 8. Thus, you need to have 2 x 8 = 16 pieces.
Every time you break the chocolate, you will get one extra piece.
Thus, to get 16 pieces, you must break it (16 - 1) = 15 times.
Answer D
Question: The price of an item is discounted 5 percent on day 1 of a sale. On day 2, the item is discounted another 10 percent, and on day 3, it is discounted an additional 15 percent. The price of the item on day 3 is what percentage of the sale price on day 1?
A.28%
B.40%
C.64.8%
D.76.5%
Answer: D.76.5%
Explanation: Let initial price be 1000
Price in day 1 after 5% discount = 950
Price in day 2 after 10% discount = 855
Price in day 3 after 15% discount = 726.75
So, Price in day 3 as percentage of the sale price on day 1 will be = 726.75/950*100 => 76.5%
Answer will definitely be (D)
Question: A and B started a partnership business investing some amount in the ratio of 7 : 5. C joined then after six months with an amount equal to that of B. In what proportion should the profit at the end of one year be distributed among A, B and C?
A.4 : 9 : 8
B.5 : 7 : 4
C.6 : 10 : 5
D.14 : 10: 5
Answer: D.14 : 10: 5
Explanation: Let the initial investments of A and B be 7x and 5x.
A : B : C = (7x x 12) : (5x x 12) : (5x x 6) = 84 : 60 : 30
= 14 : 10 : 5.
ANSWER :D
Question: 6 people meet for a business gathering. Each person shakes hands once with each other person present. How many handshakes take place?
A.30
B.21
C.18
D.15
Answer: D.15
Explanation: Let's look at the logic.
Every person shakes hand with other '5'. So, 6 people shake hands with 6X5= 30 people
But in this 30 we have counted two times the total handshakes (m shakes hand with n and n shakes hand with m)
So just divide 30/2= 15 total handshakes
Answer is D
Question: Find a two digit number, given that the sum of the digits is 9 and the difference of the digits is 3.?
A.75
B.63
C.83
D.94
Answer: B.63
Explanation: Using elimination method find which of the options fit the description of the number
... from the option only 63 meets this description
sum of digits---6+3 = 9
difference of digits ---6-3 = 3
Answer B.
Question: If 20% of 30 is greater than 25% of a number by 2, the number is:
A.16
B.24
C.20
D.32
Answer: A.16
Explanation: Explanation :
=>20/100 * 30 - 25/100 * x = 2
=> x/4 = 4 so x = 16
Answer : A
Question: 8 liters of solution is removed from 20% milk solution and 8 liters of water is added to the solution. The resulting solution has 16% milk in it. What was the initial quantity of the 20% milk solution?
A.40 Ltrs
B.50
C.60
D.70
Answer: A.40 Ltrs
Explanation: Allegation method.
Concentration of Alcohol in original sol - 20%
Concentration of Alcohol in water -- 0%
Concentration of Alcohol in final sol -- 16%
After applying allegation as shown in figure they have to be mixed in 4:1 part
1 part is given as 8 ltr, so total initial volume is 5 part = 5*8 = 40 Ltrs
ANSWER:A
Question: A person can row at 10 kmph in still water. If the velocity of the current is 2 kmph and it takes him 30 hour to row to a place and come back, how far is the place?
A.144km
B.30km
C.48km
D.12km
Answer: A.144km
Explanation: Speed of down stream = 10+2 = 12kmph
speed of upstream = 10-2 = 8kmph
Let the required distance be xkm
x/12 + x/8 = 30
2x+3x = 720
x = 144 km
Answer is A
Question: What will be the ratio of simple interest earned by certain amount at the same rate of interest for 5 years and that for 15 years?
A.3 : 2
B.1 : 3
C.2 : 3
D.3 : 1
Answer: B.1 : 3
Explanation: Explanation :
Simple Interest = PRT/100
Here Principal(P) and Rate of Interest (R) are constants
Hence, Simple Interest ∝ T
Required Ratio = Simple Interest for 5 years/Simple Interest for 15 years
=T1/T2
=5/15
=1/3
=1:3
Answer : Option B
Question: Which of the following cannot be the range of a set consisting of 5 odd multiples of 11?
A.44
B.88
C.45
D.176
Answer: C.45
Explanation: Solution: sequence of 11 lets say sequence is 11n, 11(n+1), 11(n+2), 11(n+3), 11(n+4)
so range is 11n+44-11n = 44
if we put the different values of n we will get different but the range will be multiple of 44
and only 45 is not multiple of 44
Answer : C
Question: If p is a positive integer and 10p/96 is an integer, then the minimum number of unique prime factors p could have is B:
A.B=1
B.B=2
C.B=3
D.B=4
Answer: B.B=2
Explanation: 10p/96 should resolve to a integer => 5p/48 should resolve to an integer.
Hence p/48 should resolve to a integer.
48 -- > 2^4 * 3.
Hence p should have atleast 2^4*3 for p/48 to resolve to a int.
The unique prime factors in 2^4 * 3 is 2, 3 and hence the answer is B(2).
Question: George baked a total of 150 pizzas for 7 straight days, beginning on Saturday. He baked 3/5 of the pizzas the first day, and 3/5 of the remaining pizzas the second day. If each successive day he baked fewer pizzas than the previous day, what is the maximum number of pizzas he could have baked on Wednesday?
A.5
B.6
C.4
D.3
Answer: B.6
Explanation: 3/5 of the 150 pizzas cooked on Saturday = 90 pizzas
3/5 of the remaining pizzas on Sunday = 36 pizzas
We're left with (150-90-36) =24 pizzas for the remaining 5 days. The prompt tells us that each day has FEWER pizzas than the day before it, so we can't have duplicate numbers.
M T W TH F
8 7 6 2 1 =24
W =6
B
Question: Of the people who responded to a market survey, 200 preferred Brand X and the rest preferred Brand Y. If the respondents indicated a preference for Brand X over Brand Y by ratio of 4 to 1, how many people responded to the survey?
A.80
B.160
C.250
D.350
Answer: C.250
Explanation: Ratio = 4:1 => 4x respondents preferred Brand X and x preferred Brand Y
Since, no. of respondents who preferred Brand X = 200 => 4x=200 => x=50
Hence Total no. of respondents = 200 + 50 =250
Hence C is the answer.
Question: A wheel makes 1000 revolutions in covering a distance of 88 km. Find the radius of the wheel.
A.14
B.11
C.28
D.26
Answer: A.14
Explanation: Explanation:
Distance covered in one revolution = = 88m.
Answer: A) 14
Question: P and Q can do a work in 30 days. Q and R can do the same work in 24 days and R and P in 20 days. They started the work together, but Q and R left after 2 days. How many days more will P take to finish the work?
A.10
B.15
C.42
D.20
Answer: C.42
Explanation: Let work done by P in 1 day = p,
Work done by Q in 1 day = q,
Work done by R in 1 day = r
p + q = 1/30
q + r = 1/24
r + p = 1/20
Adding all the above, 2p + 2q + 2r = 1/30 + 1/24+ 1/20 = 15/120 = 1/8
=> p + q + r = 1/16
=> Work done by P,Q and R in 1 day = 1/16
Work done by P, Q and R in 2 days = 2 × (1/16) = 2/16 = 1/8
Remaining work = 1 = 1/8 = 7/8
Work done by P in 1 day = Work done by P,Q and R in 1 day - Work done by Q and R in 1 day
= 1/16 – 1/24 = 1/48
Number of days P needs to work to complete the remaining work = (7/8) / (1/48) = 42
Option C
Question: If a computer program generates three-digit odd numbers using the numbers 9, 7, 0, 4, and 1, and the digits can be repeated, what is the probability that the number formed from the program is a multiple of three?
A. B.
C.
D.
E.
A.1/2
B.1/3
C.1/5
D.1/6
Answer: B.1/3
Explanation: 1) Lets first find TOTAL ways..
a) first/leftmost digit can be any of 5 except 0, so 4 ways
b) middle digit can be any of the 5. so 5 ways
c) the units digit can be ONLY odd- 1,7, and 9- so 3 ways
TOTAL = 4*5*3=60 ways
2) lets now find multiple of 3..
a) Digits not div by 3
7,4 and 1 will each leave remainder of 1 so they can be grouped together to form multiples of 3..
first place - 3 ways, second digit - 3 ways, and units digit ONLY 1 and 7 - 2ways
Total ways = 3*3*2=18
b) digits div by 3
9 and 0- No other digit can be used along with them as no other pair gives us sum of remainder as 3..
first place - 1 way, second digit - 2 ways, and units digit ONLY 9 - 1 way
Total ways = 1*2*1=2
TOTAL= 2+18=20
Prob =2060=132060=13
ANSWER:B
Question: The expression x#y denotes the product of the consecutive multiples of 3 between x and y, inclusive. What is the sum of the exponents in the prime factorization of 21#42?
A.23
B.24
C.25
D.26
Answer: A.23
Explanation: 21#42
= 21*24*27*30*33*36*39*42
= 3^11 * 7^2 * 2^7 * 5^1 * 11^1 * 13^1
so total is = 11+2+7+1+1+1=23
Answer A
Question: two watches (non- digital) one gained at the rate of 1 minute and the other lost at the rate of 1 minute daily were se correctly at noon on first january 1988. when will the watches indicate the same time next ?
A.dec 27 1988 noon
B.dec 27 1988 midnight
C.dec 26 1988 noon
D.dec 25 1988 noon
Answer: D.dec 25 1988 noon
Explanation: every day clock1 is getting one minute gain means it will gain 12 hours lead on 25 dec & similarly every day clock2 is getting one minute loss means it will loss 12 hours lead on 25 dec.
Now from above analysis both the clock will display the same time at dec 25 midnight.
ANSWER:D
Question: The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero ?
A.0
B.9
C.8
D.7
Answer: A.0
Explanation: Average of 20 numbers = 0.
Sum of 20 numbers = (0 * 20) = 0.
It is quite possible that 19 of these numbers may be positive and if their sum is a, then 20th number is (- a).
Answer: A
Question: The compound interest on Rs. 30,000 at 7% per annum is Rs. 4347. The period(in years) is?
A.2
B.7
C.8
D.6
Answer: A.2
Explanation: Explanation:
Amount = (30000 + 4347) = Rs. 34347
Let the time be n years. Then,
30000(1 + 7/100)n = 34347
= (107/100)n = 34347/30000 = (107/100)2
n = 2 years.
Answer:A
Question: The time taken by Mr.Dhoni to row his boat upstream is twice the time taken by him to row the same distance downstream. If the speed of the boat in still water is 72 kmph, find the speed of the stream?
A.24 kmph
B.25 kmph
C.26 kmph
D.30 kmph
Answer: A.24 kmph
Explanation: The ratio of the times taken is 2:1.
The ratio of the speed of the boat in still water to the speed of the stream = (2+1)/(2-1) = 3/1 = 3:1
Speed of the stream = 72/3 = 24 kmph.
Answer: A
Question: A dishonest dealer professes to sell goods at the cost price but uses a weight of 850 grams per kg, what is his percent?
A.28%
B.25%
C.55%
D.17.6%
Answer: D.17.6%
Explanation: 850 --- 150
100 --- ? => 17.6%
Answer: D
Question: 475.124 x 15.98 ÷ 8.001 + 33.33 = ?
A.983.578
B.659.121
C.781.189
D.656.112
Answer: A.983.578
Explanation: Explanation:
? = 475.124 x (15.98 ÷ 8.001) + 33.33
≈ (475.124 x 16/8) + 33.33 ≈ 950.248 + 33.33 ≈ 983.578
Answer: Option A
Question: The value of x.1234 - X = 4234 - 3361
A.671
B.371
C.361
D.248
Answer: C.361
Explanation: 1234-X=4234-3361
X=1234-4234+3361=361
X=361
CORRECT ANSWER : C
Question: If a: b = 17: 5, b: c = 13: 11, find a: b: c?
A.21: 65: 55
B.121: 65: 55
C.221: 65: 55
D.221: 75: 55
Answer: C.221: 65: 55
Explanation: a: b = 17: 5
b: c = 13: 11
a: b: c = 221: 65: 55
ANSWER:C
Question: Two goods trains each 820 m long are running in opposite directions on parallel tracks. Their speeds are 45 km/hr and 30 km/hr respectively. Find the time taken by the slower train to pass the driver of the faster one?
A.228
B.27.32
C.76.6
D.78.72
Answer: D.78.72
Explanation: Relative speed = 45 + 30 = 75 km/hr.
75 * 5/18 = 125/6 m/sec.
Distance covered = 820 + 820 = 1640 m.
Required time = 1640 * 6/125 = 78.72 sec.
Answer:D
Question: A car is traveling 54 kilometers per hour. How many meters does the car travel in one minute?
A.1,250 meters / minute
B.1,350 meters / minute
C.900 meters / minute
D.950 meters / minute
Answer: C.900 meters / minute
Explanation: Convert hour into minutes ( 1 hour = 60 minutes) and kilometers into meters (1 km = 1000 m) and simplify
54 kilometers per hour = 54 km/hr
= (54 * 1000 meters) / (60 minutes) = 900 meters / minute
correct answer C
Question: Find the face value of 7 in 942756
A.7
B.700
C.7000
D.70000
Answer: A.7
Explanation: Face value is the value of digit itself
face value of 7 = 7
Answer : A
Question: The mean of 50 observations is 100. But later he found that there is decrements of 13 from each observations. what is the the updated mean is ?
A.87
B.97
C.67
D.57
Answer: A.87
Explanation: 87
Answer is A
Question: The tax on a commodity is diminished by 20% and its consumption increased by 15%. The effect on revenue is?
A.7% decrease
B.8% decrease
C.9% decrease
D.6% decrease
Answer: B.8% decrease
Explanation: 100 * 100 = 10000
80 * 115 = 9200
-----------
10000-----------800
100-----------? => 8% decrease
Answer: B
Question: If goods be purchased for Rs.840 and one-fourth be sold at a loss of 20% at what gain percent should the remainder be sold so as to gain 20% on the whole transaction?
A.33 1/8%
B.33 7/3%
C.33 1/3%
D.33 8/3%
Answer: C.33 1/3%
Explanation: 1/4 CP = 210 SP = 21*(80/100) = 168
SP = 840*(120/100) = 1008
1008 - 168 = 840
3/4 SP = 630
Gain = 210
630 --- 210
100 --- ? => 33 1/3%
Answer: C
Question: Two-third of a positive number and 64/216 of its reciprocal are equal. The number is:
A.5/12
B.12/5
C.25/144
D.2/3
Answer: D.2/3
Explanation: Let the number be x. Then,
2/3 x = 64/216 * 1/x
x2 = 64/216 * 3/2 = 64/144 = 4/9
x = 2/3
ANSWER:D
Question: In 1986 the book value of a certain car was 2/3 of the original price, and in 1988 its book value was 1/2 of the original purchase price. By what percent did the book value for this car decre ase from 1986 to 1988?
A.16 2/3 %
B.25 percent
C.33 1/3 %
D.50%
Answer: B.25 percent
Explanation: 1986; 2/3
1988; 1/2
% decrease = change/original * 100
2/3−1/2 / 2/3∗100
1/6∗3/2∗100=14∗100=25
Answer: "B"
Question: In how many ways can the letters of the word, ‘TECHNOLOGY’ be arranged?
A.1804400
B.1814400
C.1714400
D.1704400
Answer: B.1814400
Explanation: The word ‘TECHNOLOGY’ contains 10 letters namely 2O, 1T, 1E, 1C, 1H, 1N, 1L, 1G, 1Y.
Therefore, Required number of ways= 10!/(2!)(1!) (1!) (1!) (1!) (1!) (1!) (1!) (1!)
= 10! / 2!
= 10*9* 8*7*6*5*4*3*2*1/2*1
= 1814400
ANSWER:B
Question: A man has Rs. 480 in the denominations of one-rupee notes, five-rupee notes and ten-rupee notes. The number of notes of each denomination is equal. What is the total number of notes that he has ?
A.45
B.60
C.75
D.90
Answer: D.90
Explanation: Let number of notes of each denomination be x.
Then x + 5x + 10x = 480
16x = 480
x = 30.
Hence, total number of notes = 3x = 90.
Answer = D
Question: If f(x) = 3x^4 - 4x^3 - 2x^2 + 5x , then f(-1) =
A.-4
B.-2
C.0
D.2
Answer: C.0
Explanation: f(-1) = 3(-1)^4 - 4(-1)^3 - 2(-1)^2 + 5(-1) = 3+4-2-5 = 0
The answer is C.
Question: The speed of the boat in still water in 12 kmph. It can travel downstream through 45 kms in 3 hrs. In what time would it cover the same distance upstream?
A.6 hours
B.5 hours
C.9 hours
D.15 hours
Answer: B.5 hours
Explanation: Speed of the boat in still water = 12 km/hr
Speed downstream = 45⁄3 = 15 km/hr
Speed of the stream = 15-12 = 3 km/hr
Speed upstream = 12-3 = 9 km/hr
Answer is B
Time taken to cover 45 km upstream = 45⁄9 = 5 hours
Question: I was facing west.I turned 125 degree in the clockwise direction and 10degree in the anticlockwise direction.Which direction am i facing now?
A.north-west
B.north
C.east
D.north-east
Answer: D.north-east
Explanation: N
W E
S
Clockwise degree - Anti-clockwise degree 115%
90% of W = N
115-90=25 degree . 25 degree of N will lie between N and E = North-East
ANSWER:D
Question: The ratio of boarders to day students at a school was originally 5 to 12. However, after a number of new boarders join the initial 220 boarders, the ratio changed to 1 to 2. If no boarders became day students and vice versa, and no students left the school, how many new boarders joined the school?
A.44
B.64
C.70
D.80
Answer: A.44
Explanation: Let x be the number of new boarders.
The ratio changed from 5:12 up to 1:2 = 6:12.
220 / (220+x) = 5/6
x = 44
The answer is A.
Question: If each side of a square is increased by 20%, find the percentage change in its area?
A.40%
B.42%
C.46%
D.44%
Answer: D.44%
Explanation: let each side of the square be a , then area = a x a
New side = 120a / 100 = 6a / 5
New area =(6a x 6a) / (5 x 5) = (36a²/25)
increased area== (36a²/25) - a²
Increase %= [(11a²/25 ) x (1/a² ) x 100]% = 44%
answer :D
Question: A father and his son are waiting at a bus stop in the evening. There is a lamp post behind them. The lamp post, the father and his son stand on the same straight line. The father observes that the shadows of his head and his son’s head are incident at the same point on the ground. If the heights of the lamp post, the father and his son are 6 metres, 1.8 metres and 0.9 metres respectively, and the father is standing 2.1 metres away from the post, then how far (in metres) is the son standing from his father?
A.0.9
B.0.75
C.0.6
D.0.45
Answer: D.0.45
Explanation: Explanation :
L is the lamp post position, F is father and S is son’s position. X is the point where the shadow falls.
LD = 0.9 = Son’s height , LB = 1.8 = Father’s height.
So AB = 6 – 1.8 = 4.2 Also BC = LF = 2.1
We observe that ∆ABC ~ ∆ADE (two triangles are similar).
Hence, the corresponding sides are proportional.
So, AB/AD = DC/DE.
4.2/5.1 = 2.1/DE.
DE = 5.1*2.1/4.2 = 5.1/2 = 2.55.
LS = DE = 2.55
FS = LS – LF = 2.55 – 2.1 = 0.45.
Answer : D