# Night Class: Quant Quiz

1. An athlete has to cover a distance of 18 km in 45 minutes. If he covers half of the distance in 1/3rd of the total time, what should be his speed (km/hr.) to cover the remaining distance in time ?
a) 15 km/h.
b) 12 km/h.
c) 18 km/h.
d) 9 km/h.
e) 15 km/h.
2. Two metro trains each 120m long are moving in opposite directions. They cross each other in 8 seconds. If one is moving twice as fast the other, the speed of the faster metro train is
a) 75 km/hr.
b) 72km/hr.
c) 45 km/hr.
d) 60 km/hr.
e) 50 km/hr.
3. An IPL team makes a score of 96 runs in the 17th inning and thus increases his average by 4. What is his average after 17th inning ?
a) 32
b) 35
c) 42
d) 36
e) 33
4. A Girl can row 30 km/hr. in still water and the river is running at 10 km/hr. If she takes 3 hour to row to a place and back, how far is the place ?
a) 16 km.
b) 30 km.
c) 40 km.
d) 50 km.
e) 60 km.
5. Anil father was 32 years of age when he was born, while his mother was 27 years, when his brother three years younger to him was born, what is the difference between age of his parents ?
a) 6 years
b) 5 years
c) 4 years
d) 3 years
e) 8 years
6. In how many ways we can select 2 persons among 10?
a) 45
b) 90
c) 40320
d) 5040
e) None of these
7. A 270 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 km/hr in 9 seconds. What is the length of the other train?
a) 320 m
b) 240 m
c) 260 m
d) 230 m
e) None of these
Directions (Q. 8-10): Read the following information carefully and answer the questions given below:
A bag contains 6 white, 4 black and 5 red balls. Two balls are drawn at random.
8. Find the probability that both the balls are red.
a) 2/21
b) 4/21
c) 1/21
d) 8/35
e) None of these
9. Find the probability that one ball is red and other is black.
a) 2/21
b) 4/21
c) 1/21
d) 8/35
e) None of these
10. Find the probability that one ball is white.
a) 44/105
b) 10/21
c) 18/35
d) 9/35
e) None of these
1. c
1/3rd of 45 min = 15 min = 9 km
2. b
D = 120 + 120 = 240 m., t = 8s.
Speed of slow train = s, faster = 2s
Total speed = 2s + s = 3s
So, 3s = 240/8 = 30 m/s.
V = 30/3 = 10 m/s.
2V = 20 m/s. or 72 km/hr
3. a
Let average after 17th innings be = x
Total runs = 17 x
Average after 16th inning = x – 4
Total runs = 16 ( x – 4)
Also, 16 (x – 4) + 96 = 17 x  x = 32
4. d
D = x km.
Speed upstream = 30 – 10 = 20 km/hr.
Speed downstream = 30 + 10 40 km/hr.
x/20 + x/40 = 3
x = 40 km
5. e
Let Anil’s age = x, Father age = x + 32
Anil’s mother = (x – 3) + 27
So diff. = ( x + 32) – ( x – 3 + 27) = 8
6. a
Total number of ways = 10C2 = 10!/8!2! = (10 * 9)/2 = 45
7. d
Distance = 200 * 5/18 * 9 = 500
Length of other train = 500 – 270 = 230 m.
8. a
Required probability = 5C2/15C2 = 10/105 = 2/21
9. b
Required probability = (5C1 * 4C1)/15C2 = 4/21
10. c
Required probability = (6C1 * 9C1)/15C2 = 18/35