Question

A journey by bus takes 45 minutes at 40 km/hr. How fast must a car go to undertake the same journey in 25 minutes?​

Answer 1

Answer:

72km/hr

Step-by-step explanation:

45min = 40km/hr

let speed for 25 min=x

25=x km/hr

This is inversely proportional, as when time increases the speed decreases and when time decreases speed increases.

=>x/40=45/25

=>x=45×40/25

=>x=72km/hr

Answer 2

SOLUTION:-

Given:

A journey by bus takes 45 minutes at 40km/hr.

To find:

Distance, a car go to undertake the same journey in 25 minutes.

Explanation:

Using the formula of inverse proportion:

•Time= 45 minutes & 25 minutes.

•Speed= 40km/hr.

Therefore,

The time decreases the speed increases;

Let the distance be R.

$= > 45 \times 40 = 25 \times R \\ \\ = > R = \frac{45 \times 40}{25} \\ \\ = > R = \frac{1800}{25} \\ \\ = > R = 72km \: hr$

Thus,

Car undertake the same journey in 25 minutes so go at 72 km/hr.

Thank you.