Question

A 5-inch candle burns down in 10 hours. After how many hours will it have burned 3 1/4 ​inches?

Answer 1

`\begin{array}{ccll} inches&hours\\ \cline{1-2} 5&10\\[1em] 3(1)/(4)&x \end{array}\implies \cfrac{5}{ ~~ 3(1)/(4) ~~ }=\cfrac{10}{x}\implies \cfrac{5}{~~ ( 13 )/( 4 ) ~~}=\cfrac{10}{x}\implies \cfrac{20}{13}=\cfrac{10}{x} \\\\\\ 20x=130\implies x=\cfrac{130}{20}\implies x=\cfrac{13}{2}\implies x=6(1)/(2)`