Question

At their annual car wash, the science club washes 30 cars in 45 minutes. At this rate, how many cars will they wash in 1 hour?

Answer 1

`"40 cars/hour"`

Explanation:

`"30 cars"/"45 minutes" = "10 cars"/"15 minutes"` (simplified).

Now, since there's `60` minutes in an hour, multiply `15` by `4`, and do the same thing to the other side. That's `40` cars in `60` minutes, or `"40 cars/hour"`