# A plane flies the 700 miles from Atlanta to Detroit in $$1\frac{1}{4}$$ hours. What is the plane's average air speed, in miles per hour?

560

Explanation

Use the formula $$r = d \div t$$. Put 700 in place of d and $$1\frac{1}{4}$$in place of t.
$$r= 700 \div 1\frac{1}{4}$$
$$r= 700 \div \frac{5}{4}$$
$$r= 700 \times \frac{4}{5} = 140 \times 4 = 560$$