Running 3 miles in 20 minutes, how many miles can one run in 50 minutes?

Question

Maria can run 3 miles in 20 minutes. At this rate, how many miles could she run in 50 minutes?

I have tried dividing 3 by 20 to get the unit rate.

Answer 1

Yes, and then multiply by that 0.15 by 50 to get the total distance of 7.5 miles.

Answer 2

Using the basic relationship $t\cdot r=d$, we have $$\require{cancel}\underbrace{50\cancel{\textrm{ min}}}_{\textrm{time}}\cdot\underbrace{\left(\frac{3\textrm{ miles}}{20\cancel{\textrm{ min}}}\right)}_{\textrm{rate}}=\underbrace{7.5\textrm{ miles}}_{\textrm{distance}}$$