RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: Find the value for x from below equation: x/3=-2?
A.-6
B.-4
C.4
D.5
Answer: A.-6
Explanation: 1. Multiply both sides by 3:
x*3/3= -2/3
2. Simplify both sides:
x = -6
A
Question: If m=9^(x−1), then in terms of m, 3^(4x−5) must be which of the following?
A.m/3
B.9m
C.9m^2
D.m^2/3
Answer: D.m^2/3
Explanation: m = 9 ^ (X-1)
m = 3 ^ (2x-2)
m^2 = 3 ^ (4x-4)
m^2/3 = 3 ^ (4x-5)
Answer D
Question: In the first half of the 20th century, the population of a particular country increased by 200 percent. In the second half of the century, the population increased by 300 percent. What was the percent increase for the 20th century as a whole?
A. 500%
B. 600%
C. 800%
D. 1100%
Answer: D. 1100%
Explanation: Say initially population was 100.
What is 200% of 100? It is 200/100 * 100 = 200.
An increase of 200% means the new population became 100 + 200 = 300
What is 300% of 300? It is 300/100 * 300 = 900
An increase of 300% means the new population now is 300 + 900 = 1200
So from 100, the population increased to 1200 i.e. an increase of 1100.
1100 is what percent of 100?
1100 = x/100 * 100
i.e. it is 1100% D
Question: Find the least number which when divided by 6, 9, 14, 21 and 24 leaves 1, 4, 9, 16 and 19 as remainders respectively, but when divided by 17 leaves no remainder.
A.11277
B.1003
C.3277
D.278
Answer: B.1003
Explanation: LCM of 6, 9, 14, 21 and 24 is 504. Required number = (504 k–5) which is divisible by 17 for the least value of k. (504 k – 5) = (493k + 11k – 5) = (17×29)k + (11k–5) Let k = 1 ⇒ (11×1 – 5) = 7 (not divisible by 17) Let k ⇒ = 2 (11×2 – 5) = 17 (divisible by 17) ∴ (17×29)k + (11k–5) is exactly divisible by 17 for k = 2. ∴ Required Number
= (504)k – 5 = (504×2) – 5 = 1003.
Answer:B
Question: The probability that a visitor at the mall buys a pack of candy is 20%. If three visitors come to the mall today, what is the probability that exactly two will buy a pack of candy?
A..343
B..147
C..189
D..096
Answer: D..096
Explanation: One case is: candy - candy - no candy
The probability is 1/5*1/5*4/5 = 4/125
There are 3 such cases, so we should multiply this probability by 3.
P(exactly 2 buy candy) = 4/125 * 3 = 12/125 = 0.096
The answer is D.
Question: find the average of all the number between 6 and 34 which are divisible by 5.
A.18
B.20
C.24
D.30
Answer: B.20
Explanation: Solution
Average = (10+15+20+25+30/5) =100/2 =20 Answer B
Question: Kevin purchased a house for Rs.61000 and a site for Rs.29000 respectively, if he sold the house for Rs.77000 and the site for Rs.19000, then find the resultant percentage of gain?
A.6.66%
B.5.55%
C.5.56%
D.6.65%
Answer: A.6.66%
Explanation: Sol.
Total CP = 90000 & total SP = 96000 ⇒ gain = SP/CP = 96000/90000 = 1.0666 = 6.66%.
Answer A
Question: 1, 6, 13, 22, 33, ?
A.46
B.44
C.35
D.65
Answer: A.46
Explanation: A
46
The pattern is + 5, + 7, + 9, + 11,....
Question: 8% people of a village in Sri Lanka died by bombardment, 15% of the remainder left the village on account of fear. If now the population is reduced to 3553, how much was it in the beginning?
A.2988
B.4543
C.4400
D.2871
Answer: B.4543
Explanation: X * (92/100) * (85/100) = 3553
X = 4543
Answer:B
Question: Find the area of the quadrilateral of one of its diagonals is 24 cm and its off sets 9 cm and 6 cm?
A.180 cm2
B.150 cm2
C.168 cm2
D.198 cm2
Answer: A.180 cm2
Explanation: 1/2 * 24(9 + 6)
= 180 cm2
Answer: A
Question: On a wedding catering service, An experienced chef can prepare a service for a wedding in 4 hours while an novice chef would finish the preparations in 16 hours.
If the catering service employs the same number of novice and experienced chefs, then how many chefs would it take to prepare a wedding service in 1 hour and 36 minutes?
A.2
B.3
C.4
D.6
Answer: C.4
Explanation: Experienced chefs work = 1 wedding/4 hours
Novice chefs work = 1 wedding/16 hours
Since we don't know the number of experienced or novice chefs but know that there is an equal number each, let the number of chefs for each group equal x
1hr and 36mins = 8/5 an hour
x/4+ x/16 = 1 wedding / (8/5)
x/4 + x/16 = 5/8
x=2
So there are 2 novice chefs and 2 experienced chefs. In total there are 4. The answer is C.
Question: If 8 parallel lines in a plane is intersected by a family of another 8 parallel lines, how many parallelograms are there in the network thus formed?
A.784
B.763
C.120
D.160
Answer: A.784
Explanation: parallelogram can formed by 2 horizontal and 2 vertical lines
for horizontal 8c2
for vertical 8c2
total parallelogram is 10 c2*8c2=28*28
=784
ANSWER:A
Question: A coin is tossed three times. What is the probability that there is at the least one tail?
A.7/8
B.31/37
C.31/18
D.31/10
Answer: A.7/8
Explanation: Let P(T) be the probability of getting least one tail when the coin is tossed three times.
= There is not even a single tail.
i.e. all the outcomes are heads.
= 1/8 ; P(T) = 1 - 1/8 = 7/8
Answer: A
Question: If X+Y = 2X+2Z, X-2Y = 2Z and X+Y+Z = 21, what is the value of Y/Z?
A.-4.
B.-2.
C.-1.7.
D.3.
Answer: A.-4.
Explanation: X+Y = 2X+2Z
Y= X+2Z---------- 1
X-2Y = 2Z
X-2Z= 2Y--------- 2
Subtracting equation 1 from equation 2
-4Z= Y
Y/Z= -4
A is the answer
Question: A, B and C enter into a partnership. A invests 3 times as much as B invests and 2/3 of what C invests. At the end of the year, the profit earned is Rs. 22000. What is the share of C?
A.Rs. 2250
B.Rs. 3375
C.Rs. 6000
D.Rs. 5625
Answer: C.Rs. 6000
Explanation: Explanation:
Let the investment of C be Rs. x.
The inverstment of B = Rs.(2x/3)
The inverstment of A = Rs. (3 × (2/3)x) = Rs. (2x)
Ratio of capitals of A, B and C = 2x : 2x/3 : x = 6 : 2 : 3
C's share = Rs. [(3/11) × 22000] = Rs. 6000
Answer: Option C
Question: Three photographers, Lisa, Mike and Norm, take photos of a wedding. The total of Lisa and Mikes photos is 60 less than the sum of Mike's and Norms. If Norms photos number 10 more than twice the number of Lisa's photos, then how many photos did Norm Take?
A.40
B.50
C.60
D.110
Answer: D.110
Explanation: L+M=M+N-60 / N=2L+10
60=M+N-L-M
60=N-L
60=2L+10-L
50=L
2(50)+10=110
D
Question: How many keystrokes are needed to type numbers from 1 to 1000?
A.3001
B.2893
C.2704
D.2890
Answer: B.2893
Explanation: Explanatory Answer
While typing numbers from 1 to 1000, there are 9 single digit numbers: from 1 to 9.
Each of these numbers requires one keystroke.
That is 9 key strokes.
There are 90 two-digit numbers: from 10 to 99.
Each of these numbers requires 2 keystrokes.
Therefore, 180 keystrokes to type the 2-digit numbers.
There are 900 three-digit numbers: from 100 to 999.
Each of these numbers requires 3 keystrokes.
Therefore, 2700 keystrokes to type the 3-digit numbers.
1000 is a four-digit number which requires 4 keystrokes.
Totally, therefore, one requires 9 + 180 + 2700 + 4 = 2893 keystrokes.
Choice B
Question: A man invests in a 16% stock at 128. The interest obtained by him is
A.22.5%
B.42.5%
C.12.5%
D.62.5%
Answer: C.12.5%
Explanation: By investing Rs 128, income derived = Rs. 16
By investing Rs. 100, income derived = = Rs.12.5
Interest obtained = 12.5%
Answer: C
Question: The product of two natural numbers is 17. Then, the sum of the reciprocals of their squares is:
A.1/289
B.289/290
C.290/289
D.289
Answer: C.290/289
Explanation: Let the numbers be a and b. Then,
ab = 17, a = 1 and b = 17
So, 1/a2 + 1/b2 = (a2 + b2)/a2 b2
= (12 + 172)/(1 * 17)2 = 290/289
ANSWER:C
Question: In the island of Hanoi is trapped a princess. To rescue her, the prince has to transfer a set of rings
numbered 1 to 7 from tower A to tower C. The rings are stacked one over the other in an order, with 1 at the top and 6 at the bottom, and have to be stacked in the same fashion on tower C. The prince can move only one ring at a time, and can store the rings in a stack, temporarily, in another tower B.Minimum how many moves of rings, between the towers, will it take the prince to arrange the rings in tower C ?
A.13
B.14
C.15
D.16
Answer: A.13
Explanation: As a total of 7 rings are to be transferred, it is mentioned that only 6 rings are present in Tower A. So, either 1 ring is present separately or there are 7 rings itself in tower A. In both cases, answer should be "13".
As a temporary stack can be used, therefore transfer top 6 rings of Tower A(or all 6 rings in case 7th ring is present separately) to Tower B in "Last in first out" order one ring at a time, so that the 6th ring is at the top of the stack in Tower B. .................-> 6 Moves made
Now, place the seventh ring at the bottom of the stack in Tower C.....1 move made here, so total moves till now= 6+1 =7
Again start transferring all 6 rings from Tower B to Tower C keeping the 6th ring above 7th ring n 1st ring at the top. ...........6 moves made here. Total moves made till now= 7+6 =13
ANSWER:A
Question: In how many ways a committee consisting of 5 women and 6 men can be formed from 8 women and 10 men?
A.A)12540
B.B)11450
C.C)11760
D.D)13250
Answer: C.C)11760
Explanation: Required number of ways = 8C5*10C5 = 8C3*10C4 = 11760
Answer is C
Question: Paul's income is 40% less than Rex's income, Quentin's income is 20% less than Paul's income, and Sam's income is 40% less than Paul's income. If Rex gave 60% of his income to Sam and 40% of his income to Quentin, Quentin's new income would be what fraction of Sam's new income?
A.11/12
B.13/17
C.13/19
D.12/19
Answer: A.11/12
Explanation: Let Rex's income = 100, then:
Rex = 100
Paul = 60
Quentin = 48
Sam = 36
Rex gives 60 dollars to sam, so now sam has 96 dollars
Rex gives 40 dollars to Quentin, so now Quentin has 88 dollars
The fraction Q/S = 11/12
ANSWER:A
Question: Ayesha's father was 38 years of age when she was born while her mother was 36 years old when her brother four years younger to her was born. What is the difference between the ages of her parents?
A.2 years
B.4 years
C.6 years
D.8 years
Answer: C.6 years
Explanation: Mother's age when Ayesha's brother was born = 36 years.
Father's age when Ayesha's brother was born = (38 + 4) = 42 years.
Required difference = (42 - 36) = 6 years.
ANSWER:C
Question: 12 points lie on a circle. How many cyclic quadrilaterals can be drawn by using these points?
A.990
B.495
C.1980
D.none
Answer: B.495
Explanation: Explanation :
For any set of 4 points we get a cyclic quadrilateral. Number of ways of choosing 4 points out of 12 points is 12C4=495Therefore, we can draw 495 quadrilaterals.
Answer : B
Question: The numbers in which of the following pairs do NOT have a pair of distinct prime divisors in common?
A.10 and 20
B.12 and 18
C.20 and 16
D.21 and 63
Answer: C.20 and 16
Explanation: 16 has only the prime 2 (16=2^4) in its prime factorization, so it can not have a PAIR of distinct prime divisors in common with ANY of the numbers.
The answer is C.
Question: Find the value of 15 + 2 â€¢ (8 â€“ 3)
A.25
B.13
C.17
D.24
Answer: A.25
Explanation: 15 + 2 â€¢ (8 â€“ 3)
= 15 + 2 (5)
= 15 + 2 *5
= 15 + 10
= 25
correct answer A
Question: A box contains 3 blue marbles, 4 red, 6 green marbles and 2 yellow marbles. If three marbles are drawn what is the probability that one is yellow and two are red?
A.12/455
B.3/19
C.14/160
D.8/79
Answer: A.12/455
Explanation: Explanation:
Given that there are three blue marbles, four red marbles, six green marbles and two yellow marbles.
When three marbles are drawn, the probability that one is yellow and two are red
= (Â²Câ‚)(â´Câ‚‚)/Â¹âµCâ‚ƒ
= (2 * 4 * 3 * 3 * 2)/(1 * 2 * 15 * 14 * 13) = 12/455
Answer: A
Question: A restaurant spends one quarter of its monthly budget for rent and two thrid of the rest for food and beverages. What percentage of the budget does the restaurant spend for food and beverages?
A.23.5%
B.50%
C.35%
D.37.5%
Answer: B.50%
Explanation: Spend on rent = 1/4
Spend on food and beverage= 2/4 of remaining = 2/3*3/4= 1/2
so 1/2= 50.0%
B is the answer
Question: A train passes a station platform in 36 sec and a man standing on the platform in 20 sec. If the speed of the train is 108 km/hr. What is the length of the platform?
A.229
B.240
C.288
D.480
Answer: D.480
Explanation: Speed = 108 * 5/18 = 30 m/sec.
Length of the train = 30 * 20 = 600 m.
Let the length of the platform be x m . Then,
(x + 600)/36 = 30 => x = 480 m.
Answer: D
Question: One side of a triangle has length 8 and a second side has length 5. Which of the following could be the area of the triangle?
I. 24
II. 20
III. 5
A.I only
B.II only
C.III only
D.II and III only
Answer: D.II and III only
Explanation: The triangle will have a maximum area when it is a right angled triangle
The largest triangle will be formed when 8 and 5 are the base and height of triangle .
Area = 1/2 * 8 * 5 = 20
There is no lower limit on the area of any triangle whose only 2 sides are known . Area> 0
So we can also have triangle with area = 5
Suppose we want to take 8 as the hypotenuse in the right angled triangle , then one of the other sides(base or height) will be less than 8 .
Hence , product will be lesser than 20 .
Answer D
Question: In june a baseball team that played 60 games had won 30% of its game played. After a phenomenal winning streak this team raised its average to 50% .How many games must the team have won in a row to attain this average?
A.20
B.30
C.24
D.12
Answer: C.24
Explanation: Explanation :
Number of matches won by the team in June: 30% of 60 = 18
After a phenomenal winning streak the average is 50%
Let the team played x matches continuously and won all of them to achieve an average winning percentage of 50%.
So total matches played by the team = (60+x)
Total matches won by the team = (18+x)
Total matches won = 50% of Total matches played
=> (18+x) = 50% of (60+x)
=> 18+x = (50/100)*(60+x)
=> 18+x = (1/2)*(60+x)
=> 36+2x = 60+x
=> x = 24
Answer : C
Question: For any 4 given numbers, which of the following is always equivalent to adding the 3 numbers together and then dividing the sum by 3?
I. Ordering the 3 numbers numerically, from highest to lowest, and then selecting the middle number.
II. Dividing each of the numbers by 3 and then adding the results together.
III. Multiplying each number by 6, adding the resulting products together, and then dividing the sum by 9.
A.I only
B.II only
C.I and II only
D.II and III only
Answer: A.I only
Explanation: Let the 3 numbers be x, y and z.
Question: Which of the following is equivalent to (x + y + z)/3
I. Ordering the 3 numbers numerically, from highest to lowest, and then selecting the middle number. --> Not always equivalent Eg: 111 and 141
II. Dividing each of the numbers by 3 and then adding the results together. --> x/3 + y/3 + z/3 = (x + y + z)/3 --> Equivalent
III. Multiplying each number by 6, adding the resulting products together, and then dividing the sum by 9. --> (6x + 6y + 6z)/9 = 2(x + y + z)/3 --> Not equivalent
Answer: A
Question: A train is 100 meter long and is running at the speed of 30 km per hour. Find the time it will take to
pass a man standing at a crossing.
A.10 seconds
B.12 seconds
C.14 seconds
D.16 seconds
Answer: B.12 seconds
Explanation: Explanation:
As we need to get answer in seconds, so never forget to convert speed into meter per second.
Speed = 30 km/hr = 30* 5/18 m/sec
= 25/3 m/sec
Distance = length of train = 100 meter
Required time =
DistanceSpeed=100253=100
∗
325=12sec
Answer: B
Question: In a certain bathtub, both the cold-water and the hot-water fixtures leak. The cold-water leak alone would fill an empty bucket inchours, and the hot-water leak alone would fill the same bucket inhhours, wherec < h. If both fixtures began to leak at the same time into the empty bucket at their respective constant rates and consequently it tookthours to fill the bucket, which of the following must be true?
I. (c/2) < t < (h/2)
II. c < t < h
III. 0 < t < h
A.a) I only
B.b) II only
C.c) I and III
D.d) I and II
Answer: C.c) I and III
Explanation: I picked numbers for this problem
C = 2 hours
H = 3 hours
C<H
2 people working together formula is
1/C + 1/H = 1/t
1/2 + 1/3 = 1/t
t = 6/5 = 1.2
Substitute the values of C, H and t in the 3 choices given below
Only 1, 3 are valid.Therefore C is the best answer
Question: A certain boxer has agreed to pay his opponent a fee of 2.5% of his total purse for every pound over the specified weight limit he weighs in. If the boxer pays his opponent a fee of $26,250 after weighing in eight pounds over the specified limit, what was the boxer's purse?
A.$65,625
B.$105,000
C.$150,000
D.$131,250
Answer: D.$131,250
Explanation: .025*8 = .2
26250/.2 = $131,250
Answer: D
Question: The least multiple of 7, which leaves a remainder of 4, when divided by 6, 9, 15 and 18 is:
A.74
B.94
C.184
D.364
Answer: D.364
Explanation: EXPLANATION
L.C.M. of 6, 9, 15 and 18 is 90.
Let required number be 90k + 4, which is multiple of 7.
Least value of k for which (90k + 4) is divisible by 7 is k = 4.
Required number = (90 x 4) + 4 = 364.
Answer D
Question: A triangle having three sides 10 cm, 17 cm, and 21 cm.A square is formed by one side lying on the longest side of the triangle.What is the maximum possible Area of the square found inside the triangle?
A.168/29
B.178/29
C.188/28
D.198/28
Answer: A.168/29
Explanation: s=1/2(10+17+21)=24
a=84
84=1/2*21*h
h=8
8/21=168/29
ANSWER:A
Question: The difference between two numbers is 2395. When the larger number is divided by the smaller one, the quotient is 6 and the remainder is 15. The smaller number is
A.120
B.239
C.476
D.523
Answer: C.476
Explanation: Let the smaller number be x.
Then, larger number = (2395 + x)
Therefore 2395 + x = (6x + 15)
‹=› 5x = 2380
‹=› x = 476.
ANSWER:C
Question: Five unbiased coin are tossed. What is the probability of getting atmost
one head?
A.31/24
B.31/34
C.31/32
D.31/35
Answer: C.31/32
Explanation: Here n(S)= 2^5
Let E=event of getting atmost one head =
n(E)= 31
P(E)=n(E)/n(S)=31/32
Answer option C)
Question: if 8^25 divided by 7 then what is reminder
A.25
B.1
C.0
D.2
Answer: B.1
Explanation: 8^25/7
8 can be written as 7*1+1
(7*1+1)^25/7
(ax+1)^n/a always gives the remainder 1
here a=7,x=1,n=25
Hence remainder is 1
ANSWER:B
Question: An integer n between 1 and 100, inclusive, is to be chosen at random. What is the probability that n(n+1) will be divisible by 4 ?
A.1/9
B.1/3
C.1/2
D.2/3
Answer: C.1/2
Explanation: n(n+1) to be divisible by 4 either n or n+1 must be a multiples of 4.
In each following group of numbers: {1, 2, 3, 4}, {5, 6, 7, 8}, ..., {97, 98, 99, 100} there are EXACTLY 2 numbers out of 3 satisfying the above condition. For example in {1, 2, 3, 4} n can be: 3, or 4. Thus, the overall probability is 2/4 = 1/2.
Answer: C.
Question: A can do a work in 15 days B in 14 days and C in 16 days . If they work on it together then in how many days required to complete the work?
A.3360/210
B.3360/21
C.3360/674
D.3360/240
Answer: C.3360/674
Explanation: Person ( A ) ( B ) ( C ) (A+B+C)
Time - (15) ( 14 ) (16)
Rate - (224) (240) (210) (674)
Work - (3360) (3360) (3360) (3360)
therefore A+B+C requires (3360/674) days to complete entire work
= 3360/674
Answer is C
Question: Find the no.of ways of arranging the boy and 3 guests at a circular table so that the boy always sits in a particular seat?
A.7!
B.3!
C.9!
D.10!
Answer: B.3!
Explanation: Ans.(B)
Sol. Total number of persons = 4 Host can sit in a particular seat in one way. Now, remaining positions are defined relative to the host. Hence, the remaining can sit in 3 places in 3P3 = 3! Ways ... The number of required arrangements = 3! x 1= 3! = 3! ways
Question: 8 litres are drawn from a cask full of wine and is then filled with water. This operation is performed three more times. The ratio of the quantity of wine now left in cask to that of the water is 16 : 65. How much wine the cask hold originally ?
A.18 litres
B.24 litres of wine
C.32 litres
D.42 litres
Answer: B.24 litres of wine
Explanation: Solution
Let the quantity of the wine in the cask originally be x litres
then, quantity of wine left in cask after 4 operations
= [x(1- 8/x)4] litres.
Therefore x(1- 8/x)4 / x = 16/81 =› (1- 8/x)4 = (2/3)2
=› (x - 8 / x) = 2/3 =› 3x - 24 = 2x =› x = 24.
Answer B
Question: January 1, 2008 is Tuesday. What day of the week lies on Jan. 1, 2009 ?
A.Sunday
B.Monday
C.Wednesday
D.Thursday
Answer: D.Thursday
Explanation: The year 2008 is a leap year. So, it has 2 odd days.
1st day of the year 2008 is Tuesday (Given)
So, 1st day of the year 2009 is 2 days beyond Tuesday.
Hence, it will be Thursday.
answer :D
Question: Find the odd man out
2, 4, 8, 16, 24, 32,64
A.2
B.4
C.24
D.32
Answer: C.24
Explanation: 2^1=2
2^2 = 4
2^3 =8
2^4=16
2^5=32
2^6=64
ANSWER:C
Question: If 148 is multiplied first by 163 and then by 236, Which of the following numbers would come at the unit's place?
A.8
B.6
C.4
D.3
Answer: C.4
Explanation: Explanation:
148 * 163 * 236 = 8 * 3 * 6 = 4 at the unit's place.
When the numbers are multiplied, the unit digit of the final product is obtained as the product of the unit digits of individual numbers.
ANSWER: C
Question: A pupil's marks were wrongly entered as 85 instead of 33. Due to that the average marks for the class got increased by half. The number of pupils in the class is :
A.30
B.104
C.20
D.25
Answer: B.104
Explanation: Let there be x pupils in the class.
Total increase in marks = (X*1/2) = X/2.
X/2 = (85 - 33)
=> X/2 = 52
=> X = 104.
ANSWER:B
Question: If in a certain code "RANGE" is coded as 12345 and "RANDOM" is coded as 123678. Then the code for the word
"MANGO" would be
A.82357
B.89343
C.84629
D.82347
Answer: D.82347
Explanation: M-8
A-2
N-3
G-4
O-7
so for mango the code is 82347
ANSWER:D
Question: Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?
A.9/209
B.9/27
C.9/20
D.9/22
Answer: C.9/20
Explanation: Explanation:
Here, S = {1, 2, 3, 4, ...., 19, 20}.
Let E = event of getting a multiple of 3 or 5 = {3, 6 , 9, 12, 15, 18, 5, 10, 20}.
P(E) = n(E)/n(S) = 9/20.
Answer: C) 9/20
Question: Amit and Ananthu can do a work in 10 days and 20 days respectively. Amit started the work and left after 2 days. Ananthu took over and completed the work. In how many days was the total work completed?
A.18 days
B.20 days
C.23 days
D.25 days
Answer: A.18 days
Explanation: Amit’s one day’s work= 1/10
Amit’s 2 day’s work = 1/10 *2 = 1/5
Work left= 1-1/5 = 4/5
Ananthu’s one day’s work= 1/20
Ananthu can do work in = 4/5 *20 = 16 days
So total days = 16+2 = 18 days
ANSWER:A
Question: A bag contains 2 red, 3 green and 2 blue balls. Two balls are drawn at random. What is the probability that none of the balls drawn is blue?
A.10/21
B.11/21
C.2/7
D.5/7
Answer: A.10/21
Explanation: Explanation:
Total number of balls = (2 + 3 + 2) = 7.
Let S be the sample space.
Then, n(S)	= Number of ways of drawing 2 balls out of 7
= 7C2 `
=	(7 x 6)/ (2 x 1)
= 21.
Let E = Event of drawing 2 balls, none of which is blue.
n(E)	= Number of ways of drawing 2 balls out of (2 + 3) balls.
= 5C2
=	(5 x 4) / (2 x 1)
= 10.
P(E) =	n(E)	/ n(S) = 10/21.
ANSWER IS A
Question: A and B go around a circular track of length 600 m on a cycle at speeds of 36 kmph and 54 kmph. After how much time will they meet for the first time at the starting point?
A.120 sec
B.198 sec
C.178 sec
D.665 sec
Answer: A.120 sec
Explanation: Time taken to meet for the first time at the starting point
= LCM { length of the track / speed of A , length of the track / speed of B}
= LCM { 600/ (36 * 5/18) , 600/ (54 * 5 /18) }
= LCM (60, 40) = 120 sec.
Answer:A
Question: In how many ways can a cricket eleven be chosen out of a batch of
15 players ?
A.1635
B.1365
C.1536
D.3651
Answer: B.1365
Explanation: Required number of ways = 15c11 = 15c(15-11) = 11c4
= 15x14x13x12/4x3x2x1 = 1365.
Answer B.
Question: Ramu bought an old car for Rs. 42000. He spent Rs. 13000 on repairs and sold it for Rs. 64900. What is his profit percent?
A.17%
B.19%
C.18%
D.14%
Answer: C.18%
Explanation: Total CP = Rs. 42000 + Rs. 13000
= Rs. 55000 and SP
= Rs. 64900
Profit(%) = (64900 - 55000)/55000 * 100
= 18%
Answer: C
Question: hree unbiased coins are tossed. What is the probability of getting at least 2 tails?
A.0.5
B.0.8
C.0.2
D.0.9
Answer: A.0.5
Explanation: Explanation:
S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}
E = {HTT, THT, TTH, TTT}
n(S) = 8
n(E) = 4
P(E) =n(E) / n(S) = 4/8 = 0.5
ANSWER: A