Question

A bicyclist rides 16 miles in 144 minutes. If she continues at this speed, how long will it take her to travel 36 miles?

Answer 1

16/144 = 36/x....16 miles to 144 minutes = 36 miles to x minutescross multiply(16)(x) = (144)(36)16x = 5184x = 5184/16x = 324 minutes 

Answer 2

find the unit rate...
144 divided by 16 is 9.
9 minutes for one mile. 
now you multiply 9 and 36 to find how long it took...
9 x 36 = 324 minutes or 5.4 hours