Question

Solve the proportions using cross products. Round to the nearest hundredth is necessary. 21miles/49hours = 15miles h hours

Answer 1

`(21)/(49)=(21:7)/(49:7)=(3)/(7)\\\\(21)/(49)=(15)/(h)\to(3)/(7)=(15)/(h)\qquad\text{cross multiply}\\\\3h=(7)(15)\\\\3h=105\qquad\text{divide both sides by 3}\\\\\boxed{h=35}\\\\Answer:\ 35\ hours`