Ashley purchased a prepaid phone card for $20
Long-distance calls cost 18 cents a minute using this card.
If the remaining credit on her card is $17.66.
How many minutes did her call last?
Let x denotes the number of minutes
Then we can set up the following equation
She initially had $20 credit, so we can need to subtract the credit that she used (that is 0.18x) from the initial credit and the result must be equal to the remaining credit that is $17.66.
Let us solve the above equation for x
Therefore, the number of minutes is 13
Her call last for 13 minutes.