distance = rate x time

d = rt

**trip there**rate = r

time = 3

d = 3r

**trip back**rate = 6

time = 4

d = 6(4)

d = 24

For the trip there and the trip back, the distances are equal.

Set the distances, 3r and 24, equal to each other.

3r = 24

r = 8

Remember, from above, r is the rate of the carrier going there.

**Average speed of trip there is 8 km/hr.**- Algebra House

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