RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: A man bets on no. 16 on a roulette wheel 14 times and losses each time. On the 15th span he does a quick calculation and finds out that the no. 12 had appeared twice in the 14 spans and is therefore, unable to decide whether to bet on 16 or 12 in the 15th span. Which will give him the best chance and what are the odds of winning on the bet that he takes?
A.32:2
B.35:1
C.33:4
D.36:23
Answer: B.35:1
Explanation: Each of the span is an independent event and the outcome of the 15th span will not depend on the outcome of the earlier spans.
Either ;35:1
B)
Question: If abc = 1 , cde = 0 , and xyu = 0, which of the following must be zero?
A.E
B.D
C.C
D.B
Answer: B.D
Explanation: abc = 1 which means neither a / b/ c is 0
c x de = 0 , we know c is not 0 from above hence either d or e must be 0.
d x a x c = 0, we know from first expression that a and c are not 0 hence d =0.
OPTION B
Question: The dimensions of an open box are 52, 40 and 29 cms. Its thickness is 2 cms. If 1 cm3 of metal used in the box weighs 0.5 gms, the weight of the box is?
A.6.882 kg
B.6.932 kg
C.8.832 kg
D.6.832 kg
Answer: D.6.832 kg
Explanation: 52 * 40 * 29 = 60320
48 * 36 * 27 = 46650
------------
13664
13664 * 1/2 = 6832 => 6.832 kg
Answer: D
Question: The radius of a semi circle is 6.83 cm then its perimeter is?
A.32.52
B.32.47
C.34.97
D.32.92
Answer: C.34.97
Explanation: 36/7 r = 6.3 = 34.97
Answer:C
Question: There are 8 men and 10 women and you need to form a committee of 5 men and 6 women. In how many ways can the committee be formed?
A.10240
B.11
C.11760
D.812
Answer: C.11760
Explanation: We need to select 5 men from 8 men and 6 women from 10 women
Number of ways to do this
= 8C5 × 10C6
= 8C3 × 10C4 [∵ nCr = nC(n-r)]
=(8×7×6 / 3×2×1) (10×9×8×7 / 4×3×2×1)
=56×210=11760
Answer : C
Question: There are 36 students in a certain geometry class. If one third of the students are boys and three fourths of the boys are under six feet tall, how many boys in the class are under six feet tall?
A.9
B.12
C.18
D.24
Answer: A.9
Explanation: Total Students = 36
One third of the students are boys = 1/3*36 = 12
Three fourths of the boys are under six feet tall = 3/4*12 = 9 ...
Therefore Number of boys in the class under six feet tall = 9 ... Answer A....
Alternatively... Number of boys in the class under six feet tall = 3/4 of 1/3 of Total Students = 3/4*1/3*36 = 9...
Answer A
Question: Nil and Ethan are brothers. They left their home
at the same time and drove to the same beach.
Nil drove at a speed of 40 miles per hour. Ethan
drove at a speed of 20 miles per hour. Nil
arrived at the beach 0.5 hour earlier than Ethan.
What is the distance between their home and the
beach?
A.30 miles
B.40 miles
C.50 miles
D.60 miles
Answer: B.40 miles
Explanation: Every hour, Nil gets ahead of Ethan 40 - 20 =
20 miles. When Nil arrived at the beach, Ethan
is only 20 × 0.5 = 10 miles behind. That tells us
they only drove 1 hour when Nil arrived at the
beach.
The distance between their home and the beach
is
Nil’s speed × Nil’s time
= 40 × 1 = 40 miles.
correct answer B
Question: A goods train runs at the speed of 72 km/hr and crosses a 250 m long platform in 26 sec. What is the length of the goods train?
A.287 m
B.278 m
C.276 m
D.270 m
Answer: D.270 m
Explanation: Speed = 72 * 5/18 = 20 m/sec.
Time = 26 sec.
Let the length of the train be x meters.
Then, (x + 250)/26 = 20
x = 270 m.
Answer:D
Question: Rs. 1300 is divided into three parts A, B and C. How much A is more than C if their ratio is 1/8:1/3:1/4?
A.Rs.224
B.Rs.216
C.Rs.100
D.Rs.300
Answer: B.Rs.216
Explanation: 1/8:1/3:1/4 = 4:8:6
3/18*1300 = 216
ANSWER:B
Question: 8 men can do a piece of work in 12 days. 4 women can do it in 48 days and 10 children can do it in 24 days. In how many days can 6 men, 4 women and 10 children together complete the piece of work?
A.5 days
B.15 days
C.28 days
D.8 days
Answer: D.8 days
Explanation: Explanation:
1 man’s 1 day’s work = 1/8 × 12 = 1/96
6 men’s 1 day’s work = 1 × 6/96 =1/16
1 woman’s 1 day’s work = 1/192
4 women’s 1 day’s work = 1/192 × 4 = 1/48
1 child’s 1 day’s work = 1/240
10 children’s 1 day’s work = 1/24
Therefore, (6 men + 4 women + 10 children)’s 1 day’s work = 1/16 + 1/48 + 1/24
= 1/8
The required No. of days = 8 days
Answer: Option D
Question: How many digits are in the number 50^8 × 8^3 × 11^2 x 10^4?
A.22
B.20
C.19
D.18
Answer: D.18
Explanation: Whenever you are asked to find the number of digits, try to bring the number in multiples of 10. This way, we can wasily calculate the umber of 0's through the powers of 10
50^8 × 8^3 × 11^2 x 10^4 = (5^2*2)^8*2^9*11^2 *10^4= 5^16*2^17*11^2*10^4 = 2*11^2*10^16*10^4 = 242*10^16 x 10^4
Hence we would have 16 trailing 0's and the three digits from 242
Total digits = 3 + 20 = 23
Correct Option: D
Question: David was born 5 years after his father's marriage. His mother is 4 years younger than his father but 20 years older than David who is 8 years old. At what age did the father get married ?
A.19 years
B.20 years
C.21 years
D.18 years
Answer: A.19 years
Explanation: Explanation:
David's present age = 8 years.
His mother's present age = (20 + 8) years = 28 years.
His father's present age = (28 + 4) years = 32 years.
His father's age at the time of David's birth = (32 - 8) years = 24 years.
Therefore David's father's age at the time of marriage = (24 - 5) years = 19 years.
Answer: A
Question: A boy multiplied 987 by a certain number and obtained 559981 as his answer. If in the answer both 98 are wrong and the other digits are correct , then the correct answer would be :
A.288889
B.556677
C.555681
D.267788
Answer: C.555681
Explanation: Explanation:
987 = 3 * 7 * 47.
So, the required number must be divisible by each one of 3, 7, 47
553681 => (Sum of digits = 28, not divisible by 3)
555181 => (Sum of digits = 25, not divisible by 3)
555681 is divisible by each one of 3, 7, 47.
Answer: C) 555681
Question: In a hotel we can order two types of varieties, but we can make 8 more varieties in home. One can choose the four varieties with two from hotel as must. Find how many ways one can order.
A.14
B.15
C.56
D.28
Answer: D.28
Explanation: 2c2*8c2=28ways
ANSWER:D
Question: Find the C.I. on a sum of Rs.1600 for 9 months at 20% per annum, interest being compounded quarterly?
A.3377
B.2889
C.2522
D.2678
Answer: C.2522
Explanation: A = 1600(21/20)3 = 2522
Answer: C
Question: The spherical ball of lead 3 cm in diameter is melted and recast into 3 spherical balls. The diameters of two of these are 1 1/2 cm and 2 cm respectively. The diameter of third ball is?
A.2.8
B.2.5
C.2.2
D.2.0
Answer: B.2.5
Explanation: 4/3 π * 3 * 3 * 3 = 4/3 π[(3/2)3 + 23 + r3]
r = 1.25
d = 2.5
Answer:B
Question: In climbing a round pole of 80 meters height, a monkey climbs 5 meters in a minute and slips 2
meters in the alternate minute. To get to the top of the pole, the monkey would take :
A.51 minutes
B.54 minutes
C.58 minutes
D.61 minutes
Answer: A.51 minutes
Explanation: a monkey climbs 5 meters in one min & slips 2m in other min.
therefore the monkey reach 3meters in 2min
3m=2min
25*3m=25*2min - >75m=50min
hence the remaining 5m jumps the monkey in 1min to reach original height
so 51 min
ANSWER:A
Question: Kim can do a work in 3 days while David can do the same work in 2 days. Both of them finish the work together and get Rs. 150. What is the share of Kim?
A.77
B.60
C.99
D.26
Answer: B.60
Explanation: Kim's wages : David's wages = Kim's 1 day work : David's 1 day work = 1/3 : 1/2 = 2:3
Kim's share = 2/5 * 150 = Rs. 60
Answer: B
Question: On dividing 22 by a number, the quotient is 7 and the remainder is 1. Find the divisor.
A.1
B.2
C.3
D.6
Answer: C.3
Explanation: d = (D-R)/Q
= (22 - 1)/7
= 21/7 = 3
C
Question: Quentin's income is 60% less than Dev's income, and Sam's income is 25% less than Quentin's income. If Dev 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.8/9
B.11/12
C.8/13
D.11/13
Answer: A.8/9
Explanation: We can take some easy numbers and make calculations simpler.
Let R ( Dev's income) = 100
Q (Quentin's income) = 40%R = 40
S (Sam's income) = 75% Q = (3/4)*40 = 30
Now, if Dev gives 40% to Quentin --> Q = 40 + 40 = 80
60% given to Sam --> S = 30+60 = 90
The ratio is : Q/S = 80/90 = 8/9=A
Question: If xy = 5 and x^2 + y^2 = 10, then x/y + y/x =
A.2
B.3 1/7
C.5 1/3
D.7
Answer: A.2
Explanation: We can make simplifying of question and get it in view: (x^2 + y^2) / xy and as we know the meaning of this parts:
x^2 + y^2 = 10
xy = 5
we can calculate the answer 10/5 -> 2 so answer is A
Question: About the number of pairs which have 18 as their HCF and 136 as their LCM, the conclusion can be
A.only one such pair exists
B.only two such pairs exist
C.such pair is not exists
D.no pairs
Answer: C.such pair is not exists
Explanation: Explanation:
HCF is always a factor of LCM. ie., HCF always divides LCM perfectly.
Correct Option: C
Question: The smallest number which when diminished by 2, is divisible by 12, 16, 18, 21 and 28 is
A.1008
B.1010
C.1022
D.1032
Answer: B.1010
Explanation: Required Number = (L.C.M of 12, 16, 18,21,28)+2
= 1008 + 2
= 1010
Answer: B
Question: if QUESTION =DOMESTIC what will b code for RESPONSE ????
A.OMESUCEM
B.OMESICSM
C.OMESICEM
D.OMESISCM
Answer: C.OMESICEM
Explanation: Q U E S T I O N
D O M E S T I C
we can see in the word'RESPONSE' only R and P are the letters whose code is not given, by having a look on options we can say code for R is O and code for P is S(bcz common in all options).now we can easily code the word 'RESPONSE'as 'OMESICEM'
ANSWER:C
Question: Adams, Smith, Derek, Alex and Bob bought movie tickets in one row next to each other. What is the probability that Bob and Adams will each sit next to each other?
A. 5%
B. 10%
C. 15%
D. 20%
Answer: B. 10%
Explanation: Possible sitting position is 5! = 120
Bob and Adams Sitting next to each other is 5 Combination 2
=5!/2!(5-2)!
=120/2(6)
=120/12
= 10
Answer = B
Question: The l ength of a rectangle is halved, while its breadth is tripled. Watis the % change in area?
A.30%
B.40%
C.50percent
D.60%
Answer: C.50percent
Explanation: Let original length = x and origina l breadth = y.
Original area = xy.
New length = x .
2
New breadth = 3y.
New area = x x 3y = 3 xy.
2 2
Increase % = 1 xy x 1 x 100 % = 50%.
2 xy
C
Question: Calculate how many days it will take for 10 boys to paint a 80 m long wall if 6 boys can paint a 70 m long wall in 8 days,
A.9.48 days
B.3.48 days
C.7.48 days
D.5.48 days
Answer: D.5.48 days
Explanation: The length of wall painted by one boy in one day = 70 / 6 * 1/8 = 1.46 m
No. of days required to paint 50 m cloth by 8 boys = 80/ 10 *1/ 1.46 = 5.48 days.
D
Question: The dimensions of a room are 25 feet * 15 feet * 12 feet. What is the cost of white washing the four walls of the room at Rs. 6 per square feet if there is one door of dimensions 6 feet * 3 feet and three WINDOWS of dimensions 4 feet * 3 feet each?
A.4000
B.345
C.5436
D.4530
Answer: C.5436
Explanation: Area of the four walls = 2h(l + b)
Since there are doors and WINDOWS, area of the walls = 2 * 12 (15 + 25) - (6 * 3) - 3(4 * 3) = 906 sq.ft.
Total cost = 906 * 6 = Rs. 5436
Answer: Option C
Question: A, B and C, each working alone can complete a job in 6, 8 and 12days respectively. If all three of them work together to complete a job and earn $2500, what will be C's share of the earnings?
A.$1200
B.$1005.8
C.$555.6
D.$1009.2
Answer: C.$555.6
Explanation: The dollars earned will be in the same ratio as amount of work done
1 day work of C is 1/12 (or 2/24)
1 day work of the combined workforce is (1/6 + 1/8 + 1/12) = 9/24
C's contribution is 2/9 of the combined effort
Translating effort to $ = 2/9 * 2500 = $555.6
Question: A boy was asked to multiply a number by 22. He instead multiplied the number by 44 and got the answer 308 more than the correct answer. What was the number to be multiplied?
A.16
B.10
C.14
D.12
Answer: C.14
Explanation: Explanation :
Let the number be x
22x + 308 = 44x
=> 44x - 22x = 308
=> 22x = 308
=> x = 308/22 = 154/11 = 14
Answer : C
Question: If a, b, c are consecutive positive integers and a<b<c, which of the following must be true?
I. c-b=1
II. abc is an even integer
III. (a+b+c)/3 is an integer
A.I, II & III
B.II
C.I and II
D.II and III
Answer: A.I, II & III
Explanation: 1. c-b=1 --> a, b, c are consequitive positive integers and a<b<c then c=b+1 --> c-b=1. So this statement is always true;
2. abc is an even integer --> out of any 3 consecutive integers at least one must be even thus abc=even. So this statement is also always true;
3. (a+b+c)/3 is an integer --> the sum of odd number of consecutive integers is ALWAYS divisible by that odd number. So this statement is also always true. Or: (a+b+c)/3=(a+a+1+a+2)/3=(3a+3)/3=a+1=integer.
Answer: A.
Question: The amount of water (in ml) that should be added to reduce 9 ml. Lotion, containing 50% alcohol, to a lotion containing 15% alcohol, is?
A.21
B.24
C.25
D.26
Answer: A.21
Explanation: 4.5 4.5
15% 85%
15% ----- 4.5
85% ------? => 25.5 - 4.5 = 21 ml
ANSWER:A
Question: A number when successively divided by 3,5 and 8 leaves remainders 1,4 and 7 respectively. Find the respective remainders R when the order of the divisors is reversed.
A.8,5,3
B.R=4,2,1
C.R=3,2,1
D.R=6,4,2
Answer: D.R=6,4,2
Explanation: My approach would be
Three Divisors : 3, 5, 8
Three Remain: 1, 4, 7
Start from the bottom of the last column i.e. from the third remainder:
Go up diagonally and multiply by the second divisor: 5*7 = 35
Go down and add the second remainder: 35 + 4 = 39
Go up diagonally and multiply by the first divisor: 39* 3 = 117
Go down and add the first remainder: 117 + 1 = 118
Divide 118 by 8, 5, 3
118/8 gives quotient = 14 and remainder = 6
14/5 gives quotient = 2 and remainder = 4
2/3 gives quotient = 0 and remainder = 2
Ans is D i.e. 6,4,2
Question: A car driver travels from the plains to the hill station, which are 200 km apart at an average speed of 30km/hr. in return trip, he covers the same distance at an average speed of 20km/hr. the average speed of the car over the entire distance of 400 km is
A.8.95km/hr
B.24.0km/hr
C.27.8km/hr
D.37.9km/hr
Answer: B.24.0km/hr
Explanation: average speed = (2*30*20)/30+20 km/hr
=24 km/hr
Answer (B)
Question: A rower can row upstream at 18 kph and downstream at 34 kph. What is the speed of the rower in still water?
A.24
B.25
C.26
D.27
Answer: C.26
Explanation: Let V be the rower's speed in still water.
Let S be the speed of the current in the stream
V-S = 18
V+S = 34
When we add the two equations, we get: 2V = 52
Then V = 26 kph.
The answer is C.
Question: The average of 15 numbers is 15. If the average of first five numbers is 14 and that of other 9 numbers is 16, then find the middle number.
A.12
B.11
C.10
D.9
Answer: B.11
Explanation: Given: Average of 15 numbers = 15, Average of 5 numbers = 14, Average of 9 numbers = 16
Average =	Total Numbers/No. of Numbers
15 =	Total Numbers/15
Therefore, total numbers = 15 x 15 = 225
Middle number = (Total numbers) – [(Average of 5 num x no of num) + ( Average of 9 num x no of num)]
= (225) – [(14 x 5) + (16 x 9)]
= (225) – [214]
= 11
Therefore, the middle number is 11
ANSWER IS B
Question: Mary's income is 60% more Than Tim's income and Tim's income is 60% less than Juan's income.What % of Juan's income is Mary's income.
A.124%
B.B.120%
C.64%
D.80%
Answer: C.64%
Explanation: Even I got 96%
J = 100
T = 100*0.4 = 40
M = 40*1.6 = 64
If Mary's income is x percent of J
M = J*x/100
x = M*100/J = 64*100/100 = 64
Ans:C
Question: A 470 m long train is running at a speed of 55 Km/hr. It crossed a platform of length 520 m in ?
A.41.1 sec
B.64.8 sec
C.31.8 sec
D.50.4 sec
Answer: B.64.8 sec
Explanation: Speed = 55 Km/hr
(to convert km/hr in to M/s)
= 55 x 5/18 M/s
Distance = 470 m + 520 m ( If questions is about train crossing a post you need to consider only the length of Train, )
= 990 m
Time = Distance / Speed
= 990 x 18 / (5 x 55)
= 64.8 sec
Ans is :B
Question: A group of students decided to collect as many paise from each member of group as is the number of members. If the total collection amounts to Rs. 59.29, the number of the member is the group is:
A.57
B.67
C.77
D.87
Answer: C.77
Explanation: Money collected = (59.29 x 100) paise = 5929 paise.
Number of members = 5929 = 77.
Answer: Option C
Question: A and B together can complete work in 8 days. A alone starts working and leaves it after working for 6 days completing only half of the work. In how many days it can be completed if the remaining job is undertaken by B?
A.4
B.8
C.5
D.12
Answer: D.12
Explanation: Explanation:
(A+B) one day work =1/8
now A does half of the work in 6 day so A can complete the whole work in 12 days
A’s one day work =1/12
B’s one day work=1/8 - 1/12= 1/24
B alone can complete the work in 24 days so half of the work in 12 days
Answer: Option D
Question: When all the students in a school are made to stand in rows of 46, 36 such rows are formed. If the students are made to stand in rows of 42, how many such rows will be formed ?
A.31
B.36
C.38
D.39
Answer: D.39
Explanation: Explanation:
Total number of students = 46 x 36
When arranged in rows of 42, number of rows formed are,
= 39.
Answer: D
Question: Complete the series 20, 19, 17, ...., 10, 5
A.15
B.16
C.13
D.14
Answer: D.14
Explanation: Explanation :
20 - 1 = 19
19 - 2 = 17
17 - 3 = 14
14 - 4 = 10
10 - 5 = 5
Answer : Option D
Question: Find the number which when increased by 11 is equal to 60 times the reciprocal of the number
A.4
B.5
C.6
D.7
Answer: A.4
Explanation: Let the number be x.
A positive number (x) increased by 11 is equal to 60 times the reciprocal of the number (1/x)
x + 11 =	60
x
x2+11x-60=0
x2+15x-4x-60=0
x(x+15)-4(x+15)=0
(x+15)(x-4)=0
x = 4
The positive number (x) = 4
A
Question: If 15 students in a class average 75% on an exam and 10 students average 95% on the same exam, what is the average in percent for all 25 students?
A.81%
B.82%
C.83%
D.84%
Answer: C.83%
Explanation: (15*75 + 10*95) / 25 = 83%
The answer is C.
Question: If v, w, x, y, and z are five different prime numbers, which of the following is the smallest possible value of v + w + x + y + z?
A.24
B.26
C.28
D.30
Answer: C.28
Explanation: The sum of the five small smallest primes numbers is 2+3+5+7+11=28.
The answer is C.
Question: If Finn was 20 months old one year ago, how old was he, in months, x months ago?
A.x − 30
B.x − 12
C.32 − x
D.24 − x
Answer: C.32 − x
Explanation: Age Today = 20 months + 12 months (1year) = 32 months
X months ago- Today's Age - X = 32 - X
Ans- C
Question: A man has Rs. 520 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.97.5
B.60
C.75
D.90
Answer: A.97.5
Explanation: Let number of notes of each denomination be x.
Then x + 5x + 10x = 520
16x = 520
x = 32.5.
Hence, total number of notes = 3x = 97.5.
Answer = A
Question: At what rate percent per annum will a sum of money double in 5 years.
A.20.0%
B.13.5%
C.11.5%
D.14.5%
Answer: A.20.0%
Explanation: Let principal = P, Then, S.I.=P and Time=8 years
Rate = [(100 x P)/ (P x 5)]% = 20.0% per annum. Answer: A
Question: A used-book dealer sells paperback books at 3 times the dealer's cost and hardback books at 4 times the dealer's cost. Last week, the dealer sold a total of 130 books, each of which had cost the dealer $1. If the gross profit (sales revenue minus the dealer's cost) on the sale of all of these books was $300, how many of the books sold were paperbacks?
A.40
B.60
C.75
D.90
Answer: D.90
Explanation: The dealer earns a profit of $2 per paperback and $3 per hardback.
If all 130 books were paperbacks, the dealer would earn a profit of $260.
Since the actual profit was $300, the dealer must have sold 40 hardbacks.
Then the number of paperbacks sold was 130-40 = 90.
The answer is D.
Question: Yesterday it took Robert 3 hours to drive from City X to City Y. Today it took Robert 2.5 hours to drive back from City Y to City X along the same route. If he had saved 15 minutes in both trips, the speed for the round trip would be 50 miles per hour. What is the distance between city X and city Y?
A. 125.5
B. 120.5
C. 150
D. 240.5
Answer: A. 125.5
Explanation: 2d/50 = 5 ( because time = 3 + 2.5 - 0.5 hrs)
=> d = 125.5
Answer - A
Question: 87th number in the series 2, 10, 26,50,……….
A.29930
B.28930
C.27960
D.26780
Answer: A.29930
Explanation: 2+8*0=2
2+8*1=10
2+8*1+8*2=26
2+8*1+8*2+8*3=50...........
87th term
2+8*1+8*2+8*3+.......................................+8*86
2+8(1+2+3+4+....................+86)
2+8*(86/2)*(1+86)= 29930
ANSWER:A
Question: Two numbers when divided by a divisor leave remainders of 228 and 352 respectively. The remainder obtained when the sum of the numbers is divided by the same divisor is 68. Find the divisor.
A.512
B.573
C.634
D.685
Answer: A.512
Explanation: Let x be the divisor.
N1 = xa + 228
N2 = xb + 352
N1 + N2 = x(a+b) + 580 = xc + 68
x(c-a-b) = 512 but we know that x > 352, thus (c-a-b) must equal 1.
The answer is A.
Question: A train 825 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 90 seconds. The speed of the train is:
A.33
B.27
C.27
D.50
Answer: D.50
Explanation: Speed of the train relative to man = (125/10) m/sec = (25/2) m/sec. [(25/2) * (18/5)] km/hr = 45 km/hr. Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr. x - 5 = 45 ==> x = 50 km/hr.
Answer:D
Question: If x and y are integers, what is the least positive number of 24x+20y?
A.2
B.3
C.4
D.6
Answer: C.4
Explanation: 24x+20y = 4(6x+5y) which will be a minimum positive number when 6x+5y = 1.
6(1) + 5(-1) = 1
Then 4(6x+5y) can have a minimum positive value of 4.
The answer is C.
Question: 100 people are attending a newspaper conference. 35 of them are writers and more than 38 are editors. Of the people at the conference, x are both writers and editors and 2x are neither. What is the largest possible number of people who are both writers and editors?
A.21
B.26
C.28
D.30
Answer: B.26
Explanation: {Total}={Writers}+{Editors}-{Both}+{Neither}.
{Total}=100;
{Writers}=35;
{Editors}>38;
{Both}=x;
{Neither}=2x;
100=35+{Editors}-x+2x --> x=65-{Editors}. We want to maximize x, thus we should minimize {Editors}, minimum possible value of {Editors} is 39, thus x={Both}=65-39=26.
Answer: B.
Question: How many different positive integers exist between 10^3 and 10^4, the sum of whose digits is equal to 2?
A.3
B.4
C.5
D.6
Answer: B.4
Explanation: 1001
1010
1100
2000
TOTAL NO. 4
B
Question: If the average (arithmetic mean) of a and b is 30 and the average of b and c is 60, what is the value of c − a?
A.25
B.60
C.90
D.140
Answer: B.60
Explanation: -(a + b = 60)
b + c=120
c-a=60
B. 60
Question: Two trains of equal are running on parallel lines in the same direction at 46 km/hr and 36 km/hr. The faster train passes the slower train in 36 sec. The length of each train is?
A.50
B.26
C.27
D.28
Answer: A.50
Explanation: Let the length of each train be x m.
Then, distance covered = 2x m.
Relative speed = 46 - 36 = 10 km/hr.
= 10 * 5/18 = 25/9 m/sec.
2x/36 = 25/9 => x = 50.
Answer: A
Question: A numberais squared and then multiplied by negative 3. The result of this operation W is equal to three times the sum of three timesaand two. What is one possible value ofa?
A.-3
B.-2
C.1
D.2
Answer: B.-2
Explanation: W=-3*a^2=3(3a+2)
a= -2 or -1
a=-2=B
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.5/20
B.9/25
C.8/20
D.9/20
Answer: D.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}
answer 9/20
Answer D
Question: The sum of five numbers is 655. The average of the first two numbers is 85 and the third number is 125. Find the average of the two numbers?
A.180
B.288
C.667
D.299
Answer: A.180
Explanation: Let the five numbers be P, Q, R, S and T.
=> P + Q + R + S + T = 655.
(P + Q)/2 = 85 and R = 125
P + Q = 170 and R = 125
P + Q + R = 295
S + T = 655 - (P + Q + R) = 360
Average of the last two numbers = (S + T)/2 = 180.
Answer:A