Question

A man runs at 10 km/h then he
voives at a certain place at
1 Pm but if the increase his.
speed 5 km/h then he reaches
their at 11 am at what speed
must be run to get their at
12 pm​

Answer 1

Answer:

12 kmph

Step-by-step explanation:

Distance travelled = x km

Time taken in first case = t hr

Runs with 10 kmph: Reached at 1 PM

Speed = Distance/Time

10 = x/t

Runs with 15 kmph: Reached at 11 AM (2 hr earlier)

15 = x/(t - 2)

Divide above two equations

10/15 = (x/t) / (x/(t - 2))

2/3 = x/t × (t - 2)/x

2/3 = 1 - 2/t

2/t = 1 - 2/3

2/t = 1/3

t = 6 hr

Substitute t = 6 in first equation

10 = x/t

10 = x/6

x = 60 km

Runs with "v" kmph: Reached at 12 PM (1 hr earlier)

v = x/(t - 1)

= 60 / (6 - 1)

= 60 / 5

= 12 kmph