Mathematics Mcqs

A person walking at 5/6th of his usual speed is 40 minutes late to his office. What is his usual travel time to his office?

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A person walking at 5/6th of his usual speed is 40 minutes late to his office. What is his usual travel time to his office?

A. 3 hours 20 minutes
B. 3 hours 15 minutes
C. 3 hours 30 minutes
D. 3 hours
Let his usual speed be x kmph, the distance to his office be y km and his usual travel time be t hrs. y = xt = (5/6)x * (t+(40/60)) Solving the equation,
t = 3.33 hrs = 3 hrs 20 minutes

Walking at 80% of his usual speed, a man is 10 mins late to his office. Find the usual time taken by hime to reach his office.

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Walking at 80% of his usual speed, a man is 10 mins late to his office. Find the usual time taken by hime to reach his office.

A. 20 minutes
B. 30 minutes
C. 40 minutes
D. 50 minutes
Let his
usual speed be x kmph
usual travel time be t hours
distance to office be d km d=xt d=(0.8x)*[t+(10/60)] xt=0.8xt+(2x/15) Solving,
t=40 minutes

At 10 a.m. two trains started traveling toward each other from stations 287 miles apart. They passed each other at 1:30 p.m. the same day. If the average speed of the faster train exceeded the average speed of the slower train by 6 miles per hour, which of the following represents the speed of the faster train, in miles per hour?

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At 10 a.m. two trains started traveling toward each other from stations 287 miles apart. They passed each other at 1:30 p.m. the same day. If the average speed of the faster train exceeded the average speed of the slower train by 6 miles per hour, which of the following represents the speed of the faster train, in miles per hour?

A. 38
B. 40
C. 44
D. 48
Let the speed of the faster train be x miles per hour and
the distance travelled by it when it meets the slower train be y miles. Time taken by the faster train to cover y miles
= Time taken by the slower train to cover (287-y) miles
= 3.5 hours (y/x) = (287-y)/(x-6) = 3.5 Solving, x = 44 miles/hr

Three towns X, Y, and Z are on a river which flows uniformly. Y is equidistant from X and Z. If a boats man rows from X to Y and back in 10 hours and X to Z in 4 hours, find the ratio of speed of the boats man in still water to the speed of the current.

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Three towns X, Y, and Z are on a river which flows uniformly. Y is equidistant from X and Z. If a boats man rows from X to Y and back in 10 hours and X to Z in 4 hours, find the ratio of speed of the boats man in still water to the speed of the current.

A. 2:5
B. 5:3
C. 3:5
D. 1:2
X ———— Y ———— Z
If ‘d’ is the distance between X and Y, then ‘d’ is the distance between Y and Z.
Now the total time for the batsman to row from X to Z is 4 hours. Therefore, time to row from X to Y is 2 hours.
Also the time for the boats man to row from X to Y and back is 10 hours. Hence, time required to row from Y to X is 8 hours.
If, a: speed of boats man in still water
b: speed of the river
d/(a + b) = 2; d/(a – b) = 8
2*(a + b) = 8*(a – b)
a + b = 4a – 4b
3a = 5b
a:b = 5:3

A and B go cycling in the same direction with speeds of 6 km/hr and 12 km/hr. A car from behind passes them in 9 and 10 seconds respectively. What is the speed of the car?

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A and B go cycling in the same direction with speeds of 6 km/hr and 12 km/hr. A car from behind passes them in 9 and 10 seconds respectively. What is the speed of the car?

A. 22 km/hr
B. 33 km/hr
C. 66 km/hr
D. 44 km/hr
The relative speed of A and B is 6 km/hr = 1.67 m/s
As the car passes A after 10s, the distance between A and B after 10s (i.e. at 11th second) is the distance covered by car in 1 second.
Therefore, at t = 11, d = 1.67 * 11
d = 18.33 m
v = d/t = 18.33/1 = 18.33m/s
v = 66 km/hr

A man takes 5 hours 45 min in walking to a certain place and riding back. He would have gained 2 hours by riding both ways. The time he would take to walk both ways is_________?

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A man takes 5 hours 45 min in walking to a certain place and riding back. He would have gained 2 hours by riding both ways. The time he would take to walk both ways is_________?

A. 11 hrs
B. 8 hrs 45 min
C. 7 hrs 45 min
D. 9 hts 20 min
Given that time taken for riding both ways will be 2 hours lesser than
the time needed for waking one way and riding back
From this, we can understand that
time needed for riding one way = time needed for waking one way – 2 hours
Given that time taken in walking one way and riding back = 5 hours 45 min
Hence The time he would take to walk both ways = 5 hours 45 min + 2 hours = 7 hours 45 min

In a journey of 24 miles, two thirds of the distance was travelled with a speed of 40 mph and the remaining with 60 mph. How much time did the journey take?

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In a journey of 24 miles, two thirds of the distance was travelled with a speed of 40 mph and the remaining with 60 mph. How much time did the journey take?

A. 14.4 minutes
B. 20 minutes
C. 28.8 minutes
D. 32 minutes
(2/3)*24=16 miles Time taken to cover the first 16 miles
= (16/40) hours
= 24 minutes Time taken to cover the next 8 miles
= (8/60) hours
= 8 minutes Time taken for the entire journey
= 32 minutes