Question

Charmaine purchased a prepaid phone card for $25. Long distance calls cost 16 cents a minute using this card. Charmaine used her card only once to make a long distance call. If the remaining credit on her card is $21.16, how many mintues did her call last?

Answer 1

Determine the credit of the card used to complete a call.

$25-21.16=3.84$

So, $3.84 is used to complete a call. 16 cents is equivalent to $0.16

Determine the minutes of the last call.

$\begin{gathered} 0.16x=3.84 \\ x=\frac{3.84}{0.16} \\ =24 \end{gathered}$

So, last call ends after 24 minut