A rocket test model burns fuel at a constant rate. It uses 2 2/5 gallons of fuel every 3/10 of a minute. How many gallons of fuel will it burn in 1 1/2 ?

Answer: 12 gallons

Step-by-step solution

Step 1: Convert mixed numbers to improper fractions

First, we convert all given mixed numbers into improper fractions. The fuel burned is 225=2×5+25=1252\frac{2}{5} = \frac{2 \times 5 + 2}{5} = \frac{12}{5} gallons, and the total time is 112=1×2+12=321\frac{1}{2} = \frac{1 \times 2 + 1}{2} = \frac{3}{2} minutes.

Step 2: Find the fuel consumption rate per minute

To find the rate per unit minute, divide the fuel used, 125\frac{12}{5} gallons, by the time taken, 310\frac{3}{10} minute. Dividing by a fraction is equivalent to multiplying by its reciprocal, which gives 125×103=4×2=8\frac{12}{5} \times \frac{10}{3} = 4 \times 2 = 8 gallons per minute.

Step 3: Calculate fuel burned in the given time

Multiply the burning rate of 88 gallons per minute by the total time of 32\frac{3}{2} minutes. We have 8×32=4×3=128 \times \frac{3}{2} = 4 \times 3 = 12 gallons.

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