1. If a certain computer is capable of printing 4900 monthly credit card bills per hour, while a new model is capable of printing at a rate of 6600 per hour, the old model will take approximately how much longer than the new model to print 10000 bills?
Answer: 31 minutes
Explanation:
Old model is capable of printing at a rate of 4900 per hour
New model is capable of printing at a rate of 6600 per hour
Old model time taken to print 10000 cards = 10000/4900 = 100/49
New model time taken to print 10000 cards = 10000/6600 = 100/66
Old model – new model: 100/49 - 100/66 = 1700 /(49 × 66) = 850/(49 × 33) = 0.525 hrs => 31 mins
Therefore, the old model will take approximately 31 mins longer than the new model to print 10000 bills
2. 3 men and 8 women complete a task in same time as 6 men and 2 women do. How much fraction of work will be finished in same time if 4 men and 5 women will do that task.
1) 5/6
2) 6/13
3) 7/9
4) 11/12
5) 11/15
6) 13/14
Answer: 6
Explanation:
3 m + 8 w = 6 m + 2 w
3 m = 6 w
1 m = 2 w
Therefore 3 m + 8 w = 14 w
4 m + 5 w =13 w
Answer is 13/14
3. How can a cake(circular) be cut into 8 pieces by making just 3 cuts?
Explanation:
Cut the cake using three mutually perpendicular planes. It leaves 8 pieces, one each in each octant.
4. A number of cats got together and decided to kill between them 999919 mice. Every cat killed an equal number of mice. Each cat killed more mice than there were cats. How many cats do you think there were?
Answer:
Explanation: 991
999919 = 1000000 – 81 = $1000^2$ – $9^2$ = (1000 + 9)(1000 – 9) = 1009 × 991.
Since there were more mice than there were cats, 991 cats killed 1009 mice each.
5. An alloy of zinc and copper contains the metals in the ratio 5 : 3. The quantity of zinc to be added to 6 kg of the alloy so that the ratio of the metal may be 3 : 1 is:
A)3
B)6
C)8
D)9
Answer: C
Explanation:
In sixteen kg of alloy 10 kg of zinc and 6 kg copper is present
To make the ratio 3:1 we must add 8 kg of zinc to make it 18 kg of zinc and 6 kg copper
So answer is 8.
6. A class consists of 100 students, 25 of them are girls and 75 boys; 20 of them are rich and remaining poor; 40 of them are fair complexioned. The probability of selecting a fair complexioned rich girl is
Answer: 1/50
Explanation:
The probability of selecting girl is: 25/100 = 1/4
The probability of selecting rich is: 20/100 = 1/5
The probability of selecting fair complexioned is: 40/100 = 2/5
Three are independent;probability of rich and fair complexioned girl is:
(1/4) ×(1/5) × (2/5) = 1/50
7. If one-third of one-fourth of a number is 15, then three-tenth of that number is:
A. 35
B. 36
C. 45
D. 54
Answer: D
Explanation:
The number is 1/3 of 1/4 is =15 then 1/3 × 1/4 = 15
Number is 180 then 180 × 3/10 = 54
8. 100 oranges are bought at the rate of Rs. 350 and sold at the rate of Rs. 48 per dozen. The percentage of profit or loss is:
A) 100/7% gain
B) 15% gain
C) 100/7% loss
D) 15 % loss
Answer:A
Explanation:
C.P. of 100 orange=350
S.P. of 12 is 48 i.e, 4 of each now of 100 will be 400
So profit = 400 – 350 = 50
profit = $\dfrac{{profit × 100\% }}{{cp}}$ i.e 100/7% gain
9. If 3/p = 6 and 3/q = 15 then p – q = ?
A) 1/3
B) 2/5
C) 3/10
D) 5/6
E) None of the above
Answer: C
Explanation:
$\dfrac{{3}}{{p}}$ = 6 , p = $\dfrac{{3}}{{6}}$ = $\dfrac{{1}}{{2}}$and
$\dfrac{{3}}{{q}}$ = 15 , q = $\dfrac{{3}}{{15}}$ = $\dfrac{{1}}{{5}}$ then
p – q = 1/2 – 1/5 = 3/10
10. Two trains leaving from two station 50 miles away from each other with constant speed of 60 miles per hour, approaches towards each other on different tracks. if length of each train is 1/6 mile. when they meet How much time they need to pass each other totally ?
Answer: 10 seconds
Explanation:
The trains are coming towards each other so their relative speed is 60 + 60 = 120 mph
In this case the distance would be addition of lengths of trains.i.e 1/6 + 1/6 = 1/3 m
T = $\dfrac{{d}}{{s}}$ = $\dfrac{{1/3}}{{120}}$ = $\dfrac{{1}}{{1360}}$ h
Answer: 31 minutes
Explanation:
Old model is capable of printing at a rate of 4900 per hour
New model is capable of printing at a rate of 6600 per hour
Old model time taken to print 10000 cards = 10000/4900 = 100/49
New model time taken to print 10000 cards = 10000/6600 = 100/66
Old model – new model: 100/49 - 100/66 = 1700 /(49 × 66) = 850/(49 × 33) = 0.525 hrs => 31 mins
Therefore, the old model will take approximately 31 mins longer than the new model to print 10000 bills
2. 3 men and 8 women complete a task in same time as 6 men and 2 women do. How much fraction of work will be finished in same time if 4 men and 5 women will do that task.
1) 5/6
2) 6/13
3) 7/9
4) 11/12
5) 11/15
6) 13/14
Answer: 6
Explanation:
3 m + 8 w = 6 m + 2 w
3 m = 6 w
1 m = 2 w
Therefore 3 m + 8 w = 14 w
4 m + 5 w =13 w
Answer is 13/14
3. How can a cake(circular) be cut into 8 pieces by making just 3 cuts?
Explanation:
Cut the cake using three mutually perpendicular planes. It leaves 8 pieces, one each in each octant.
4. A number of cats got together and decided to kill between them 999919 mice. Every cat killed an equal number of mice. Each cat killed more mice than there were cats. How many cats do you think there were?
Answer:
Explanation: 991
999919 = 1000000 – 81 = $1000^2$ – $9^2$ = (1000 + 9)(1000 – 9) = 1009 × 991.
Since there were more mice than there were cats, 991 cats killed 1009 mice each.
5. An alloy of zinc and copper contains the metals in the ratio 5 : 3. The quantity of zinc to be added to 6 kg of the alloy so that the ratio of the metal may be 3 : 1 is:
A)3
B)6
C)8
D)9
Answer: C
Explanation:
In sixteen kg of alloy 10 kg of zinc and 6 kg copper is present
To make the ratio 3:1 we must add 8 kg of zinc to make it 18 kg of zinc and 6 kg copper
So answer is 8.
6. A class consists of 100 students, 25 of them are girls and 75 boys; 20 of them are rich and remaining poor; 40 of them are fair complexioned. The probability of selecting a fair complexioned rich girl is
Answer: 1/50
Explanation:
The probability of selecting girl is: 25/100 = 1/4
The probability of selecting rich is: 20/100 = 1/5
The probability of selecting fair complexioned is: 40/100 = 2/5
Three are independent;probability of rich and fair complexioned girl is:
(1/4) ×(1/5) × (2/5) = 1/50
7. If one-third of one-fourth of a number is 15, then three-tenth of that number is:
A. 35
B. 36
C. 45
D. 54
Answer: D
Explanation:
The number is 1/3 of 1/4 is =15 then 1/3 × 1/4 = 15
Number is 180 then 180 × 3/10 = 54
8. 100 oranges are bought at the rate of Rs. 350 and sold at the rate of Rs. 48 per dozen. The percentage of profit or loss is:
A) 100/7% gain
B) 15% gain
C) 100/7% loss
D) 15 % loss
Answer:A
Explanation:
C.P. of 100 orange=350
S.P. of 12 is 48 i.e, 4 of each now of 100 will be 400
So profit = 400 – 350 = 50
profit = $\dfrac{{profit × 100\% }}{{cp}}$ i.e 100/7% gain
9. If 3/p = 6 and 3/q = 15 then p – q = ?
A) 1/3
B) 2/5
C) 3/10
D) 5/6
E) None of the above
Answer: C
Explanation:
$\dfrac{{3}}{{p}}$ = 6 , p = $\dfrac{{3}}{{6}}$ = $\dfrac{{1}}{{2}}$and
$\dfrac{{3}}{{q}}$ = 15 , q = $\dfrac{{3}}{{15}}$ = $\dfrac{{1}}{{5}}$ then
p – q = 1/2 – 1/5 = 3/10
10. Two trains leaving from two station 50 miles away from each other with constant speed of 60 miles per hour, approaches towards each other on different tracks. if length of each train is 1/6 mile. when they meet How much time they need to pass each other totally ?
Answer: 10 seconds
Explanation:
The trains are coming towards each other so their relative speed is 60 + 60 = 120 mph
In this case the distance would be addition of lengths of trains.i.e 1/6 + 1/6 = 1/3 m
T = $\dfrac{{d}}{{s}}$ = $\dfrac{{1/3}}{{120}}$ = $\dfrac{{1}}{{1360}}$ h
