Question

Measurement & Conversion (d=rt) Two children run in opposite directions. One runs at a speed of 4 mph while the other runs at 6 mph. How long will it take before they are 5 miles apart?

Answer 1

1/2 hour

Explanation:

speed = distance/time

distacne = speed × time

d = r ×t

for a speed of 4mph,

d = 4 × t = 4t

for a speed of 6 mph,

d = 6 × t = 6t

since they are going in opposite direction, we add there distance together

4t + 6t = their distance apart

their distance apart = 5 miles

4t + 6t = 5 miles

10t = 5

t = 5/10

t = 1/2 hour

It will take them 1/2 hour before they are 5 miles apart