Question

The Miller Family shares a cell phone plan. Last month, Jodie used 3/4 of the minutes. Her son Billy used 4/5 of the remaining minutes. What fraction of the minutes did Billy use?

Answer 1

Answer: The fraction of the minutes did Billy use = $\dfrac15$.

Step-by-step explanation:

Let x = Total minutes given in the plan.

Last month, Jodie used $\dfrac34$ of the minutes.

Remaining minutes = $x-\dfrac34x=\dfrac14x$

Billy used = $\dfrac45(\dfrac14x)=\dfrac{x}{5}$  minutes

Fraction of the minutes used by Billy = $\dfrac{\dfrac{x}{5}}{x}=\dfrac15$

Hence, the fraction of the minutes did Billy use = $\dfrac15$.