Mathematics Mcqs

Excluding stoppages, the average speed of a bus is 54 kmph and including stoppages, it is 45 kmph. For how many minutes does the bus stop per hour?

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Excluding stoppages, the average speed of a bus is 54 kmph and including stoppages, it is 45 kmph. For how many minutes does the bus stop per hour?

A. 9
B. 10
C. 12
D. 20
Due to stoppages, the bus travels only 45 kms in an hour (9 kms less). To cover a distance of 9 km at a speed of 54 kmph, time taken
= 9/54 = 1/6 hrs = 10 mins.

If a boat is rowed downstream for 50 km in 5 hours and upstream for 24 km in 6 hours, what is the speed of the boat and the river?

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If a boat is rowed downstream for 50 km in 5 hours and upstream for 24 km in 6 hours, what is the speed of the boat and the river?

A. (7 , 3) km/hr
B. (6 , 4) km/hr
C. (10 , 4) km/hr
D. None of these
If x: speed of boats man in still water
y: speed of the river
Downstream speed (Ds) = x + y
Upstream speed (Us) = x – y
x = (Ds + Us) / 2
y = (Ds – Us) / 2
In the above problem Ds = 10 ; Us = 4
x = (10 + 4) / 2 = 14/2 = 7 km/hr
y = (10 – 4)/2 = 6/2 = 3 km/hr

Taimoor left for his school at 6 am by foot and walked at the rate of 2 kmph. After reaching his school he found it was closed and immediately turned back and started walking back to his home at 3 kmph. If he reached his home at 9 am, find the distance between his school and his home.

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Taimoor left for his school at 6 am by foot and walked at the rate of 2 kmph. After reaching his school he found it was closed and immediately turned back and started walking back to his home at 3 kmph. If he reached his home at 9 am, find the distance between his school and his home.

A. 2.5 km
B. 7.2 km
C. 7 km
D. 3.6 km
Average speed of Taimoor = (2*2*3)/(2 + 3) = 2.4 km/hr
If d is he distance between the school and Taimoor’s home, then total distance walked by Taimoor = 2d, and the total time taken is 3 hours
2.4 = 2d/3
7.2 = 2d
d = 3.6 km

A train can travel 50% faster than a car. Both start from point A at the same time and reach point B 75 kms away from A at the same time. On the way, however, the train lost about 12.5 minutes while stopping at the stations. What is the speed of the car?

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A train can travel 50% faster than a car. Both start from point A at the same time and reach point B 75 kms away from A at the same time. On the way, however, the train lost about 12.5 minutes while stopg at the stations. What is the speed of the car?

A. 80 kmph
B. 102 kmph
C. 120 kmph
D. 140 kmph

A and B walk around a circular track. A and B walk at a speed of 2 rounds per hour and 3 rounds per hour respectively. If they start at 8 a.m. from the same point in opposite directions, how many times shall they cross each other before 9.30 a.m.?

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A and B walk around a circular track. A and B walk at a speed of 2 rounds per hour and 3 rounds per hour respectively. If they start at 8 a.m. from the same point in opposite directions, how many times shall they cross each other before 9.30 a.m.?

A. 5
B. 6
C. 7
D. 8
Relative speed = Speed of A + Speed of B (∴ they walk in opposite directions)
= 2 + 3 = 5 rounds per hour
=> They cross each other 5 times in 1 hour and 2 times in 1/2 hour
Time duration from 8 am to 9.30 am = 1.5 hour
Hence they cross each other 7 times before 9.30 am

If a man walks at 6 kmph, he can reach his destination at 9:00 am. However, he walks a little slower and reaches only at 10:00 am. If the distance to his destination was 12 km, at what speed did he walk?

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If a man walks at 6 kmph, he can reach his destination at 9:00 am. However, he walks a little slower and reaches only at 10:00 am. If the distance to his destination was 12 km, at what speed did he walk?

A. 5 kmph
B. 4 kmph
C. 4.5 kmph
D. 3 kmph
If he travels at 6 kmph,
time taken to reach = 12/6 = 2 hours But he takes 3 hours.
Speed = 12/3 = 4 kmph

Asghar traveled from his house to his office at 10 km/hr and returned at rate of 9 km/hr. Rohit travelled through the same path both ways at 12 km/hr and took 10 minutes less than Asghar. What is the distance between Asghar’s house and his office?

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Asghar traveled from his house to his office at 10 km/hr and returned at rate of 9 km/hr. Rohit travelled through the same path both ways at 12 km/hr and took 10 minutes less than Asghar. What is the distance between Asghar’s house and his office?

A. 3000m
B. 7500m
C. 3750m
D. 7000m
Average speed for Raj is: v = (2*9*10)/(9+10) = 180/19 km/hr = 50/19 m/s
Average speed for Rohit = 12 km/hr = 10/3 m/s
Now, v = d/t
As d is same, v*t = constant.
Let, t be the time taken by Rohit in seconds. Hence, time taken by Raj is (t +600)s
50/19 * (t + 600) = 10/3 * t
150*(t + 600) = 190t
t = 2250s
Let d be the distance between the house and the office
2d = 2250 * 10/3
2d = 7500 m
d = 3750m

An aeroplane covers a certain distance at a speed of 240 kmph in 5 hours. To cover the same distance in 5/3 hours, it must travel at a speed of:_________?

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An aeroplane covers a certain distance at a speed of 240 kmph in 5 hours. To cover the same distance in 5/3 hours, it must travel at a speed of:_________?

A. 660 km/hr
B. 680 km/hr
C. 700 km/hr
D. 720 km/hr
Distance = Speed x Time = 240 x 5 km
New time =5/3 hr
Hence, new speed = Distance/Time =240*5/5/3
=240×3=720 km/hr

A man covered a certain distance at some speed. If he had moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. What is the the distance in km?

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A man covered a certain distance at some speed. If he had moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. What is the the distance in km?

A. 36
B. 52
C. 41
D. 40