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Starting at home, Ishaan traveled uphill to the gift store for 18 minutes at just 10 mph. He then traveled back home along the same path downhill at a speed of 30 mph.

What is his average speed for the entire trip from home to the gift store and back?

User Roshin Jay
by
7.8k points

1 Answer

5 votes
The formula to find speed:


speed = distance / time

We first need to find the distance to gift store:
18/60 × 10
=3miles

We can then find the time he used down hill:
3÷30×60
=0.1×60
=6 minutes

In total he walked:
3x2
=6miles

We can then find his average speed by dividing the distance by total time used:
=6÷(6+18)/60
=6÷24/60
=15mph

The answer is 15mph.

Hope it helps!
User Valenterry
by
8.2k points