Answer:
He traveled at 72km/hr during the rain
Step-by-step explanation:
<em>Question is not well formatted. See comment</em>
Given
--- distance
--- total time
Let his speed from city A till the rain starts on his return trip be
Let his speed from city during the rain be
So:
Required
Calculate
From the question, we understand that; he drives the whole 400 km and 2/5 of 400 km at
The distance covered during this period is:
And the time during this period is:
So, the distance during the rain is:
And the time during the rain is:
So, we have:
--- distance covered before the rain
--- distance covered when raining
---- time spent before the rain
--- time spent in the rain
Speed is calculated as:
Make distance the subject
So:
Recall that:
Make the subject
The expression becomes:
Collect like terms
Solve for