divelab/Sys2Bench huggingface dataset:
Question: Tap 'A' can fill the tank completely in 6 hrs while tap 'B' can empty it by 12 hrs. By mistake, the person forgot to close the tap 'B', As a result, both the taps, remained open. After 6 hrs, the person realized the mistake and immediately closed the tap 'B'. In how much time now onwards, would the tank be full?
Options:
A)2 hours
B)3 hours
C)5 hours
D)1 hour
E)None of these
Rationale: Explanation :
Tap A can fill the tank completely in 6 hours
=> In 1 hour, Tap A can fill 1⁄6 of the tank
Tap B can empty the tank completely in 12 hours
=> In 1 hour, Tap B can empty 1⁄12 of the tank
i.e., In one hour, Tank A and B together can effectively fill 1⁄6 - 1⁄12 = 1⁄12 of the tank
=> In 6 hours, Tank A and B can effectively fill 1⁄12 × 6 = 1⁄2 of the tank.
Time taken to fill the remaining 1−(1/2) = 1/2 of the tank = (1/2)/(1/6) = 3 hours. Answer : Option B
Answer: B
Question: Find the area of trapezium whose parallel sides are 20 cm and 18 cm long, and the distance between them is 5 cm?
Options:
A)827 cm2
B)216 cm2
C)95 cm2
D)80 cm2
E)176 cm2
Rationale: Area of a trapezium = 1/2 (sum of parallel sides) * (perpendicular distance between them)
= 1/2 (20 + 18) * (5)
= 95 cm2
Answer:C
Answer: C
Question: Albert invested an amount of $8000 in a fixed deposit scheme for 2 years at compound interest rate 5% p.a. How much amount will Albert get on maturity of the fixed deposit?
Options:
A)$8100
B)$8820
C)$8800
D)$8810
E)$8825
Rationale: Amount = 8000 x (1 + 5/100)^2)
= 8000 x 21/20 x 21/20
=8820.
Answer B)$8820
Answer: B
Question: Two persons start running simultaneously around a circular track of length 600 m from the same point at speeds of 20 km/hr and 10 km/hr. When will they meet for the first time any where on the track if they are moving in opposite directions ?
Options:
A)27 sec
B)87 sec
C)67 sec
D)72 sec
E)37 sec
Rationale: Explanation:
Time taken to meet for the first time anywhere on the track
= length of the track / relative speed
= 600 / (20 + 10)5/18 = 600 x 18 / 30 x 5 = 72 seconds.
Answer: D
Answer: D
Question: The batting average of a particular batsman is 60 runs in 46 innings. If the difference in his highest and lowest score is 170 runs and his average excluding these two innings is 58 runs, find his highest score.
Options:
A)179
B)367
C)189
D)177
E)191
Rationale: Explanation:
Total runs scored by the batsman = 60*46 = 2760 runs
Now excluding the two innings the runs scored = 58*44 = 2552 runs
Hence the runs scored in the two innings = 2760 â€“ 2552 = 208 runs.
Let the highest score be x, hence the lowest score = x â€“ 170
x + (x - 170) = 208
2x = 378
x = 189 runs
ANSWER: C
Answer: C
Question: At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 10 gallon tank of gasoline and travels for 5 hours at 50 miles per hour, the amount of gasoline used would be what fraction of a full tank?
Options:
A)3/25
B)5/6
C)7/12
D)2/3
E)25/36
Rationale: Gas used = (5 hours)*(50 miles/hour)*(1 gallon/30 miles) = 8+1/3 gallons
Portion used = (8+1/3) / 10 = 5/6
Ans B
Answer: B
Question: Nicky and Cristina are running a race. Since Cristina is faster than Nicky, she gives him a 36 meter head start. If Cristina runs at a pace of 6 meters per second and Nicky runs at a pace of only 3 meters per second, how many seconds will Nicky have run before Cristina catches up to him?
Options:
A) 15 seconds
B) 18 seconds
C) 25 seconds
D) 30 seconds
E) 12 seconds
Rationale: used pluging in method
say t is the time for cristina to catch up with Nicky, the equation will be as under:
for Nicky=N=3*t+36
for Cristina=C=6*t
@t=12, N=72 C=72 right answer
ans:E
Answer: E
Question: Two sets of 3 consecutive positive odd integers have exactly one integer in common. The sum of the integers in the set with greater numbers is how much greater than the sum of the integers in the other set?
Options:
A)4
B)7
C)8
D)12
E)it cannot be determined from the information given.
Rationale: A=(1,3,5), sum of this=9
B=(5,7,9), sum of this=21,
The differenct between 21-9=12
Hence,12 is the answer i.e.D
Answer: D
Question: How many real roots does the equation x^3y+16xy+64y=0 have if y < 0?
Options:
A)0
B)1
C)2
D)3
E)Infinite
Rationale: x^3y+16xy+64y=0
=> y ( x^2 + 16x + 64) = 0
=> y (x+8)^2 = 0
if y<0 , then x=-8
So although there are 2 factors , they are the same x=-8 .
The equations has 1 distinct real root .
Answer B
Answer: B
Question: Krishan and Nandan jointly started a business. Krishan invested three times as Nandan did and invested his money for double time as compared to Nandan. Nandan earned Rs. 4000. If the gain is proportional to the money invested and the time for which the money is invested then the total gain was?
Options:
A)Rs.28,028
B)Rs.28,002
C)Rs.28,028
D)Rs.28,000
E)Rs.28,039
Rationale: 3:1
2:1
------
6:1
1 ----- 4000
7 ----- ? => Rs.28,000
Answer: D
Answer: D
Question: If 244,312 football shoes need to be placed in boxes and each box can contain at most 5 pair of football shoes. How many pair of football shoes will be in the last unfilled box?
Options:
Options:
A)1football shoes
B)3 football shoes
C)4 football shoes
D)2 football shoes
E)9 football shoes
Rationale: The number of football shoes that can be placed in boxes of 5 football shoes is the first number that is divisible by 5 that occurs before 244,312.
In order to divide the sum in 5 parts, the amount must be divisible by 5
Divisibility rule of 5: the last digit is 5 or 0.
last digit of digits of 244,312 is 2 and 2 is not divisible by 5
Hence, we need to remove 2 to this number for it to be divisible by 5
Correct Option: D
Answer: D
Question: If a square mirror has a 20-inch diagonal, what is the approximate perimeter W of the mirror, in inches?
Options:
A) 40
B) 60
C) 80
D) 100
E) 120
Rationale: if you draw the square and diagonal inside the square. u can see square becomes part of two triangles opposite to each other.
And We know the property of the triangle, addition of two sides of triangle must be greater than its diagonal in order to complete the triangle. And each side must be less than 20 and perimeter W must be less than 80, so we can eliminate answer choice C, D and E.
so Side 1 + side 2 > 20, that means Side 1 or Side 2 must be > 10. so we can eliminate the answer choice A.
Now we are left with is B
Answer: B
Question: Find the simple interest on Rs. 69,000 at 16 2/3% per year for 9 months.
Options:
A)7500
B)6500
C)8625
D)9500
E)None of them
Rationale: P = Rs.69000,R = 50/3% p.a and T = 9/12 years = 3/4years.
Simple Interest = (P*R*T)/100 = Rs.(69,000*(50/3)*(3/4)*(1/100))= Rs.8625
Answer is C.
Answer: C
Question: The sum of three consecutive numbers is 252. The greatest among these three number is:
Options:
A)45
B)80
C)85
D)55
E)40
Rationale: Let the numbers be x, x + 1 and x + 2
Then,
x + (x + 1) + (x + 2) =252
3x = 252
x = 83
Greatest number, (x + 2) = 85
ANSWER:C
Answer: C
Question: Solution A is 20% salt and Solution B is 60% salt. If you have 30 ounces of solution A and 60 ounces of solution B, in what ratio could you mix Solution A with Solution B to produce 50 ounces of a 50% salt solution?
Options:
A)6:4
B)6:14
C)4:4
D)4:6
E)1:3
Rationale: Forget the volumes for the time being.
You have to mix 20% and 80% solutions to get 50%. This is very straight forward since 50 is int he middle of 20 and 80 so we need both solutions in equal quantities. If this doesn't strike, use
w1/w2 = (A2 - Aavg)/(Aavg - A1)
w1/w2 = (60 - 50)/(50 - 20) = 1/3
So the volume of the two solutions will be equal. Answer has to be 1:3
E.
Answer: E
Question: A certain club has exactly 5 new members at the end of its first week. Every subsequent week, each of the previous week's new members (and only these members) brings exactly J new members into the club. If y is the number of new members brought into the club during the twelfth week, which of the following could be y?
Options:
A) 5^1/12
B) 3^11 * 5^11
C) 3^12 * 5^12
D) 3^11 * 5^12
E) 60^12
Rationale: At the end of the first week, there are 5 new members;
At the end of the second week, there are 5J new members (since each 5 new members from the previous week brings J new members);
At the end of the third week, there are 5J^2 new members (since each 5J new members from the previous week brings J new members);
...
At the end of the twelfth week, there are 5J^11 new members (since each 5J^10 new members from the previous week brings J new members).
We are given that 5J^11=y. Out of the answers only D yields integer value for J: 5J^11=3^11 * 5^12 --> J=3*5=15.
Answer: D.
Answer: D
Question: The difference between a number and its two-fifth is 510. What is 60% of that number?
Options:
A)512
B)510
C)514
D)516
E)518
Rationale: Let the number be x. Then,
x - 2/5 x = 510
x = (510 * 5)/3 = 850
60% of 850 = 510.
Answer:B
Answer: B
Question: Find the principle on a certain sum of money at 5% per annum for 4 years if the amount being Rs.1120?
Options:
A)933
B)1067
C)1977
D)1056
E)1097
Rationale: 1120 = P [1 + (5*4)/100]
P= 933
Answer: A
Answer: A
Question: A, B and C are partners in a business. Their capitals are respectively, Rs.5000, Rs.6000 and Rs.4000. A gets 30% of the total profit for managing the business. The remaining profit is divided among three in the ratio of their capitals. In the end of the year, the profit of A is Rs.200 more than the s um of the profits of B and C. Find the total profit.
Options:
A)s.4500
B)s.5200
C)s.1800
D)s.Rs.3000
E)s.5000
Rationale: A:B:C = 5:6:4
Let the total profit = 100 - 30 = 70
5/15 * 70 = 70/3
A share = 70/3 + 30 = 160/3
B + C share = 100 - 160/3 = 140/3
A-(B+C) = 160/3 - 140/3 = 20/3
20/3 ---- 200
100 ---- ? => 3000
ANSWER:D
Answer: D
Question: Solution A is 20% pottasium and Solution B is 80% pottasium. If you have 30 ounces of solution A and 60 ounces of solution B, in what ratio could you mix Solution A with Solution B to produce 50 ounces of a 50% pottasium solution?
Options:
A)6:4
B)6:14
C)4:4
D)4:6
E)3:7
Rationale: Forget the volumes for the time being.
You have to mix 20% and 80% solutions to get 50%. This is very straight forward since 50 is int he middle of 20 and 80 so we need both solutions in equal quantities. If this doesn't strike, use
w1/w2 = (A2 - Aavg)/(Aavg - A1)
w1/w2 = (80 - 50)/(50 - 20) = 1/1
So the volume of the two solutions will be equal. Answer has to be 4:4=C
Answer: C
Question: A team bought a total of 567 balls. If each player on the team bought at least 24 balls, then what is the greatest possible number of players on the team?
Options:
A)21
B)22
C)23
D)24
E)25
Rationale: 567/24=23 plus remainder.
The answer is C.
Answer: C
Question: P is 6 times greater than Q then by what per cent is Q smaller than P?
Options:
A)84%
B)85.5%
C)80%
D)83.33%
E)None
Rationale: Solution: Let Q = 10.
Then, P = 60.
Q is 50 less than P.
Q, % less than P = (50 /60)*100 = 83.33%.
Alternative Method
10 (Q)==(6 times greater)==> 60(P)==x%↓(Less than Q)==>10 (Q).
Now, x = 50*100/60 = 83.33%.
Answer: Option D
Answer: D
Question: Right now, the ratio between the ages of Sandy and Molly is 4:3. After 6 years, Sandy’s age will be 38 years. What is Molly's age right now?
Options:
A)15
B)18
C)21
D)24
E)27
Rationale: Now, Sandy is 38 - 6 = 32
Molly's age is (3/4) * 32 = 24
The answer is D.
Answer: D
Question: The least number which should be added to 2520 so that the sum is exactly divisible by 5,6,4 and 3 is :
Options:
A)3
B)18
C)23
D)33
E)43
Rationale: Solution
L.C.M. of 5,6,4 and 3 = 60. on dividing 2520 by 60, the remainder is 42.
∴ Number to be added = (60-42) = 18. Answer B
Answer: B
Question: If a profit of Rs.12000 is to be divided among three partners A,B and C in the ratio 5:3:4 then share of B is
Options:
A)Rs.2000
B)Rs.4000
C)Rs.3000
D)Rs.5000
E)Rs.7000
Rationale: B=3/12*12000=3000
ANSWER:C
Answer: C
Question: If m > 1 and n = 2^(m+2), then 4^m =
Options:
A)16n^2
B)4n^2
C)n^2
D)n^2/4
E)n^2/16
Rationale: n = 2^(m+2) = 2^m*4
2^m = n/4
4^m = (2^m)^2 = (n/4)^2 = n^2/16
The answer is E.
Answer: E
Question: Two out of five employees are capable of doing a certain task. Sixty percent of the five employees, including the two who are capable, are assigned to a project involving this task. what percentage of employees assigned to the project are not capable?
Options:
A)43.33%
B)33.33%
C)13.33%
D)38.33%
E)23.33%
Rationale: Given 60% of 5 employees including 2 who are capable of doing task.
60% of 5 employeees
= 60/100 * 5
= 3 employees
===> 2 employees who are capable of doing the task and one employee who is not capable.
percentage of employees assigned who are not capable
= 1/3 * 100
= 33.33%
ANSWER:B
Answer: B
Question: What is the ratio of (1/4 )to the power 3 and (1/4) to the power4
Options:
A)1:2
B)1:3
C)1:4
D)2:1
E)4:1
Rationale: 1/4^3/1/4^4=4/1=4:1
ANSWER:E
Answer: E
Question: A thief steels a car at 8a.m. and drives it at 50kmph. The theft is discovered at 9a.m. and the owner sets off in another car at 70 kmph. When will he overtake the thief?
Options:
A)9a.m.
B)9.30a.m.
C)1130a.m.
D)11.45a.m.
E)10.15a.m.
Rationale: Suppose the thief overtakes x hours after 8a.m.
Distance covered by the thief in x hrs = distance covered by the owner in (x-1 hours)
50x = 70(x-1)
20x = 70
x = 7/2 hrs
Thief is overtaken at 11.30a.m.
Answer is C
Answer: C
Question: Two persons starting from the same place walk at a rate of 5kmph and 7kmph respectively. What time will they take to be 24km apart, if they walk in the same direction?
Options:
A)17 hrs
B)22 hrs
C)25 hrs
D)12 hrs
E)14 hrs
Rationale: The relative speed of the boys = 7kmph â€“ 5kmph
= 2 kmph
Distance between them is 24 km
Time= 24km / 2 kmph = 12 hrs
Answer : D.
Answer: D
Question: a, b are positive integers. The remainder of a to be divided by 8 is 3 and the remainder of b to be divided by 6 is 5.
Which is possible to be the remainder of a*b to be divided by 48
Options:
A)a) 2
B)b) 6
C)c) 8
D)d) 15
E)e) 20
Rationale: Two ways to do it...
a=8x+3..
b=6y+5..
1) convenient way..
Take x and y as 0, and you will get a*b as 3*5=15
Answer : D
Answer: D
Question: Perimeter of an equilateral and isosceles is 45 and 40 respectively. At least one of the sides of isosceles is equal to the equilateral. What's the base of isosceles triangle?
Options:
A)7
B)8
C)9
D)10
E)11
Rationale: 10 units
as other 2 sides will be 15,15 units.
ANSWER:D
Answer: D
Question: For any non-zero a and b that satisfy |ab| = -ab and |a| = a, |b-3| + |ab-b| =
Options:
A)ab-4
B)|ab|+4
C)2a-4b
D)b-3ab
E)ab+2ab+1
Rationale: given |ab|=-ab a*b is negative , |a|=a, so a is positive hence b is negative since ab is negative.
assume a=1,b=-1 |b-3|= 4, |ab-b|=2; |b-3|+|ab-b|=6.
test case :c)
2a-4b= 6
test a) |-1|-4= -3
test b) 1+4=5
hence corect answer: C
Answer: C
Question: If 4+X < (2+5X)/3, which of the following is correct?
Options:
A)X < -5.
B)X > -5.
C)X > 5.
D)-5 < X < 0.
E)0 < X < 5.
Rationale: 4+X < (2+5X)/3
12+3X < 2+ 5X
10 < 2X
5<X
C is the answer
Answer: C
Question: Gali builds a tower using only red, green, and blue toy bricks in a ratio of 4:3:1. She then removes 1/2 of the green bricks and adds 1/3 more blue bricks, reducing the size of the tower by 14 bricks. How many red bricks will she need to add in order to double the total number of bricks used to build the original tower?
Options:
A)82
B)96
C)110
D)120
E)192
Rationale: Gali want to double the original amount of blocks, not just the red blocks
the original tower had 96 bricks, the new tower has 82 bricks and the question is asking how many extra red blocks are needed to build a tower of 192 bricks (double the original: 96*2).
192-82 = 110
so 110 bricks need to be added to the new 82 brick tower to double the original.
They worded the question ashow many red bricks need to be addedbut really it could be any colour just that 110 more bricks need to be there to equal 192=C
Answer: C
Question: How much is 80% of 40 is greater than 4/5 of 25?
Options:
A)12
B)27
C)18
D)12
E)81
Rationale: (80/100) * 40 – (4/5) * 25
32 - 20 = 12
Answer:D
Answer: D
Question: The price of a integrated declines by 67 percent every 6 months. At this rate, approximately how many years will it take for the price of an $81 integrated chip to reach $1?
81- 67% * 81 = 27 approx
27 - 0.67*27 = 9 approx
9- 0.67*9 = 3 approx
3-0.67*3= $1 approx
Options:
A)1.5 years
B)2 years
C)3 years
D)13 years
E)13.5 years
Rationale: not sure whether you like this:
81 - (81 x 67%)/3 = 81 - (81 x 2) / 3 = 27 = 81 / 31 = 81 / (3x3x3x3) = 81 / 3^4
so the time = 4 x 6 months = 24 months or 2 years. answer is B
Answer: B
Question: The probability that a number selected at random from the first 50 natural numbers is a composite number is
Options:
A)17/26
B)17/25
C)17/20
D)17/22
E)17/21
Rationale: The number of exhaustive events = ⁵⁰C₁ = 50.
We have 15 primes from 1 to 50.
Number of favourable cases are 34.
Required probability = 34/50 = 17/25.
nswer: B
Answer: B
Question: In a class of students, 1/2 of the number of girls is equal to 1/6 of the total number of students. What is the ratio of boys to girls in the class?
Options:
A)1/2
B)2/3
C)2/1
D)3/2
E)4/3
Rationale: (1/2)G=(1/6)(B+G)
6G=2B+2G
4G=2B
B/G=2/1.
The answer is C.
Answer: C
Question: The cash difference between the selling prices of an article at a profit of 4% and 2% is Rs. 3. The ratio of the two selling prices is?
Options:
A)52:51
B)52:53
C)52:50
D)22:56
E)52:51
Rationale: Let C.P. of the article be Rs. x.
Then, required ratio = 104% of x / 102% of x
= 104/102 = 52/51 = 52:51
Answer: A
Answer: A
Question: How many 3 digit numbers can be formed which are divisible by 3 using the numerals 0, 1, 2, 3, 4, 5 (WITH REPETITION)
Options:
A)216
B)133
C)240
D)600
E)305
Rationale: Divisibilty rule for 3: Sum of all digits is a multiple of 3
Selections for the above to be valid
1,2,3,4,5
No of possible ways = 5*5*5 = 125
0,1,2
No of possible ways = 2*2*1 = 4
0,4,5
No of possible ways = 2*2*1 = 4
Total = 8+125 = 133
Option
B
Answer: B
Question: The length of the bridge, which a train 140 meters long and travelling at 45 km/hr can cross in 30 seconds, is:
Options:
A)230
B)244
C)245
D)238
E)235
Rationale: Speed = (45 * 5/18) m/sec = (25/2) m/sec. Time = 30 sec. Let the length of bridge be x meters. Then, (140 + X)/30 = 25/2 ==> 2(140 + X) = 750 ==> X = 235 m.
Answer: Option E
Answer: E
Question: Last year, the price of a vacation package was P. At the beginning of this year, the price went up 20%. Lucas used a travel voucher to purchase the vacation package at 30% off this year’s price. In terms of P, how much did Lucas pay?
Options:
A) P + 10
B) 1.1*P
C) 1.12*P
D) 0.80*P
E) 0.84*P
Rationale: Last year price = P;
This year price = 1.2P;
Lucas used a travel voucher to purchase the vacation package at 30% off this year’s price, thus he paid (1 - 0.3)*1.2P = 0.84P.
Answer: E.
Answer: E
Question: Three taps A, B and C can fill a tank in 12, 15 and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternately, the tank will be full is?
Options:
A)6 hrs
B)6 2/3 hrs
C)7 hrs
D)7 1/2 hrs
E)5 hrs
Rationale: (A + B)'s 1 hour work = (1/12 + 1/15) = 3/20
(A + C)'s 1 hour work = (1/12 + 1/20) = 2/15
Part filled in 2 hrs = (3/20 + 2/15) = 17/60
Part filled in 6 hrs = 3 * 17/60 = 17/20
Remaining part = 1 - 17/20 = 3/20
Now, it is the turn of A and B and 3/20 part is filled by A and B in 1 hour.
Total time taken to fill the tank = (6 + 1) = 7 hrs.
ANSWER:C
Answer: C
Question: The present ages of three persons in proportions 4 : 1 : 5. Eight years ago, the sum of their ages was 56. Find their present ages (in years).
Options:
A)8, 20, 28
B)16, 28, 36
C)16, 28, 35
D)16, 28, 34
E)32, 8, 40
Rationale: Let their present ages be 4x, 1x and 5x years respectively.
Then, (4x - 8) + (1x - 8) + (5x - 8) = 56
10x = 80
x = 8.
Their present ages are 4x = 32 years, 1x = 8 years and 5x = 40 years respectively.
Answer:E
Answer: E
Question: Find the average of first 5 multiples of 5?
Options:
A)10
B)15
C)12.5
D)13
E)21
Rationale: average = (5+10+15+20+25)/5 = 15
Answer is B
Answer: B
Question: A class contains five juniors and five seniors. If one member of the class is assigned at random to present a paper on a certain subject, and another member of the class is randomly assigned to assist him, what is the probability W that both will be juniors?
Options:
A)1/10
B)1/5
C)2/9
D)2/5
E)1/2
Rationale: I think you're right. The other way to do it (but the long way) is to figure out the probability that it is not two Juniors.
2 seniors = P(Senior) * P(Senior) = 2/9
1 Senior and 1 Junior = (1/2) *(5/9)*2 = 5/9
Probability that it is not two Juniors is 5/9+2/9 = 7/9 so the probability W that it is two juniors is 1- (7/9) = 2/9.C
Answer: C
Question: A fruit salad mixture consists of apples, peaches, and grapes. There are 3 times as many pounds of apples as grapes and 2.5 times as many pounds of peaches as grapes. If a mixture that has an average (arithmetic mean) of 26 pounds per fruit, how many more pounds of apples than grapes does the mixture have?
Options:
A)24
B)11
C)9
D)6
E)5
Rationale: A+P+G= 26*3
A=3G
P=2.5G
3G+2.5G+G= 26*3
G= 26*3/6.5= 12
A= 12*3=36
Difference = 36-12=24
'A' is the answer
Answer: A
Question: If 6 men and 8 boys can do a piece of work in 10 days while 26 men and 48 boys can do the same in 2 days, the time taken by 15 men and 20 boys in doing the same type of work will be:
Options:
A)4 days
B)5 days
C)6 days
D)8 days
E)2 days
Rationale: Let 1 man's 1 day's work = x and 1 boy's 1 day's work = y.
Then, 6x + 8y =1/10	and 26x + 48y =1/2
Solving these two equations, we get : x =1/100 and y =1/200
(15 men + 20 boy)'s 1 day's work =(15/100+20/200)	=1/4	.
15 men and 20 boys can do the work in 4 days.
ANSWER:A
Answer: A
Question: The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero?
Options:
A)87
B)15
C)17
D)19
E)16
Rationale: 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:D
Answer: D
Question: By selling 50 meters of cloth. I gain the selling price of 15 meters. Find the gain percent?
Options:
A)42 7/7%
B)42 5/8%
C)42 6/4%
D)42 6/8%
E)42 1/7%
Rationale: SP = CP + g
50 SP = 50 CP + 15 SP
35 SP = 50 CP
35 --- 15 CP gain
100 --- ? => 42 6/7%
Answer: D
Answer: D
Question: In boring a well 50 m deep, the cost is
Rs.4/– for the first meter. The cost of each successive meter
increases by Rs.2/–. What is the cost of boring the entire well?
Options:
A)1650
B)2650
C)3650
D)4650
E)2850
Rationale: For successive meters the cost of boring will be 4, 6, 8, 10, ......., which forms an arithmetic series with terms n=50, first term a=4 & difference d=2
So Sum=(n/2)[2a+(n-1)d]= Total cost of boring
=(50/2)[2*4+(50-1)*2]=25(8+98)
= 2650
ANSWER:B
Answer: B
Question: In a panel of 10 light bulbs, the odds of any light bulb to burn out are 0.07 at any given 10 minutes. Should a light bulb burn out, the whole panel would instantly turn off. What are the odds that the panel would be turned off within the first 10 minutes after it was switched on?
Options:
A)1-0.03^10
B)1-0.93^10
C)(1-0.93)^10
D)0.06
E)1-10*0.07
Rationale: ans B.
Prob that light will not turned off = 0.93^10. Hence prob (turn off) = 1 - prob (not turn off).
Answer: B
Question: A Train requires 10 seconds to pass a pole while it requires 40 seconds to cross a stationary train which is 300 mtrs long. Find the speed of the train.
Options:
A)36kmph
B)42kmph
C)48kmph
D)52kmph
E)64kmph
Rationale: In 10s the train crosses the pole and in 40 sec the train crosses one more stationary train
In 30 sec the train travels a distance of 300 mtrs
Speed = 300/30 = 10 m/s = 10 * 18/5 = 36 kmph
Answer: A
Answer: A
Question: The ratio of the number of females to males at a party was 1:2 but when 4 females and 4 males left, the ratio became 1:3. How many people were at the party originally?
Options:
A)20
B)22
C)24
D)26
E)28
Rationale: The total number of people are x females + 2x males.
3*(x-4) = 2x - 4
x = 8
There were 3x = 24 people at the party originally.
The answer is C.
Answer: C