Question

Christy drove 132 miles in 2 3/4 hours what was her average speed in miles per hour?

Answer 1

let's first convert the mixed fraction to improper, and get their quotient.

`\bf \stackrel{mixed}{2(3)/(4)}\implies \cfrac{2\cdot 4+3}{4}\implies \stackrel{improper}{\cfrac{11}{4}} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \cfrac{132}{~~(11)/(4)~~}\cfrac{miles}{hours}\implies \cfrac{(132)/(1)}{~~(11)/(4)~~}\implies \cfrac{132}{1}\cdot \cfrac{4}{11}\implies \cfrac{132}{11}\cdot \cfrac{4}{1}\implies 12\cdot 4\implies 48(miles)/(hours)`