Answer:
3/2 gal = 1.5 gal
Explanation:
The amount of gas used in a given time is found by multiplying the rate of gas usage by the time.
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rate of gas usage
(60 mi/h) / (20 mi/gal) = 3 gal/h
usage in 30 min
We know that 30 minutes is 1/2 hour, so the usage in 1/2 hour is ...
(1/2 h) × (3 gal/h) = 3/2 gal = 1.5 gal