Question

A girl goes to her office for work which is 50 miles. She goes to her office few distance by bicycle and remaining by train. The speed of bicycle is 15 mph and that of train is twice of the bicycle. If she spend 20 min. more on bicycle, then total time taken by her from going to office from her home? A 1 hr 30 min 2 hr 30 min 2 hr 20 min D 2 hr 50 min

Answer 1

The speed of bicycle is 15 mph

The speed of the train = 2x15 = 30 mph

She travels x miles on the bicycle

She travel (50 - x ) in the train


Time taken on the bike = x/15
Time taken in the train = (50-x)/30


If she spend 20 min. more on bicycle (20 minutes = 1/3 hours)


x/15 – (50-x)/30 = 1/3
2x – 50 + x = 10
3x = 60
x = 20

Total time = x/15 + (50-x)/30

                = 20/15 + (50-20)/30
                = 4/3 + 1
                = 2 (1/3) hours


= 2 hours 20 minutes

Answer 2

Answer:

Step-by-step explanation:

The speed of bicycle is 15 mph

The speed of the train = 2x15 = 30 mph

She travels x miles on the bicycle

She travel (50 - x ) in the train

Time taken on the bike = x/15

Time taken in the train = (50-x)/30

If she spend 20 min. more on bicycle (20 minutes = 1/3 hours)

x/15 – (50-x)/30 = 1/3

2x – 50 + x = 10

3x = 60

x = 20

Total time = x/15 + (50-x)/30

= 20/15 + (50-20)/30

= 4/3 + 1

= 2 (1/3) hours

= 2 hours 20 minutes