Lucys bike rental

Question

On a beach trip Lucy rents a bike from wheels by waves where they can rent bikes for 12 dollars plus 3 dollars per hour if Lucy spent 30 dollars how many hours did she rent the bike

Answer 1

Use a ratio. Let x = hours that bike is rented.

So, 3 hours/12 dollars= x hours/30 dollars

Then x = (3)(30)/(12) = 7.5 hours