Respuesta :
Glenda has been over charged by $3.40 for her purchase. Below is the solution:
First you have to multiply the prices for frames and mats by number of pieces:
5.89 x 4 = 23.56
12.95 x 4 = 51.80
Then add amount:
23.56 + 51.80 = 75.36
Then multiply by 6.5%
$75.36 * 6.5% = $4.90
$75.36 + $4.90 = $80.26
$80.26 + $8.20 = $88.46
$91.86- $88.46 = $3.40