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3 years ago

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If a bicyclist is traveling at a speed of 10 km/h, he will be late by 1 hour. If he will travel at a speed of 15 km/h, then he w

ill arrive an hour early. How fast should he travel to arrive on time?

1 answer:

Svetllana [295]3 years ago

5 0

Answer:

The speed should he travel to arrive on time is 12 km/h

Step-by-step explanation:

Given as :

Let the time taken by bicyclist = T h

If bicyclist travel with speed 10 km/h,

Then the time taken by him = ( T + 1 ) hours

Again

If bicyclist travel with speed 15 km/h ,

Then the time taken by him = ( T - 1 ) hours

Now Let The distance cover by bicyclist = D km = Speed × Time

So, As The distance cover is same for both case

∴ 10 × (T + 1 ) = 15 × (T - 1)

Or, 2 × (T + 1 ) = 3 × (T - 1)

Or, 2 T + 2 = 3 T - 3

Or, 3 +2 = 3 T - 2 T

∴ T = 5 hour

So, Distance cover by bicyclist = D = 10 × (5 + 1 )

Or, D = 60 km

So, new speed of bicyclist with time 5 hour and distance cover 60 km

New Speed = $\frac{Distance}{Time}$

Or, New Speed = $\frac{60}{5}$

∴ New Speed = 12 km/h

Hence The speed should he travel to arrive on time is 12 km/h Answer

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