Question

Hello just trying to make sure I did this right

Answer 1

Part A

the total cost is

3*(31.99)+2*(13.80)=$123.57

answer part a is $123.57

Part B

we have that

the total cost using the coupon is

123.57-10=$113.57

Using proportion

Remember that

123.57 represent 100%

so

100/123.57=x/10

solve for x

x=10*100/123.57

x=8%

answer is 8%

Part 2

with paying 7% tax

the total cost is $123.57

Remember that

100%+7%=107%=107/100=1.07

so

the total cost is

$123.57(1.07)=$132.22