Question

Two persons are start walking in opposite directions at 5 km/h and 4 km/h respectively. in how many hours will they be 45km apart?

Answer 1

Two persons start walking in opposite direction at 5km and 4km per hour respectively.
In one hour the distance between them is 9 km as given in the question.
So to be 45 km apart the time they take will be 45/9 = 5 hours.
Hope it helps.

Answer 2

Thus, Time taken to $45km$ apart is $5h$

Step-by-step explanation:

Given,

Two persons are start walking in opposite directions at $5\frac{km}{h}$ and $4\frac{km}{h}$ respectively and total distance is $45km$

Relative speed$=(5+4)=9\frac{km}{h}$

We have,

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

⇒$Time=\frac{45}{9}$

∴$Time=5h$

∴ Time taken to $45km$ apart is $5h$