Activity Rylee shopped at a clothing store, where she spent $36.50 plus 8% tax. Then, she spent $25 to refuel her car at the gas station. Finally, she bought groceries worth $23.50. At the grocery checkout, she handed over a coupon for a 20% discount on her purchase.

Complete the following steps to help Rylee find the net change to her banking account balance.

Part B
Write an expression that represents the net change in Rylee’s bank account balance after paying for fuel at the gas station.

Part C
Use decimal numbers to write an expression that represents the net change in Rylee’s bank account balance after paying for groceries.

Part D
Finally, use decimal numbers to write an expression that represents the net change in Rylee’s bank account balance for her entire shopping trip. Use your answers from parts A through C to guide you.

Part E
Simplify the expression in part D to find the net change in Rylee’s bank account balance. Express your answer as a decimal number.​

A)

Rylee bought $36.50 in clothes. This money is leaving her bank account, so represent the amount with a negative sign: -$36.50.

The tax on her purchase is 8%, so the tax amount is 0.08 × -$36.50. The expression that represents the net change in her bank account is -$36.50 + (0.08 × -$36.50).

Further simplify the expression by factoring -$36.50 from both terms:

-$36.50 + (0.08 × -$36.50)

=

-$36.50(1 + 0.08)

=

-$36.50(1.08).

B)

Rylee spent $25 for fuel at the gas station. This money is leaving her bank account, so represent the amount with a negative sign: -$25.

C)

The original price of Rylee’s groceries was $23.50. This money is leaving her bank account, so represent the amount with a negative sign:
-$23.50.

Rylee got a 20% discount on her purchase. In other words, she got 20% of her money back. The expression that represents the net change in her bank account is
-$23.50 – (-$23.50 × 0.2).

Further simplify the expression by factoring -$23.50 from both terms:


-$23.50 – (-$23.50 × 0.2)  = -$23.50(1 – 0.2)

             = -$23.50(0.8).

D)

clothing store:

-$36.50(1.08) or -$36.50 + (0.08 × -$36.50)

gas station:

-$25

grocery store:

-$23.50(0.8) or -$23.50 – (-$23.50 × 0.2)

After adding the three expenses:

-36.5 + (-36.5)(0.08) + (-25) + (-23.5) − (-23.5)(0.2) or

(-36.5)(1.08) + (-25) + (-23.5)(0.8).

E)

(-36.5)(1.08) + (-25) + (-23.5)(0.8) = -$83.22

enjoy :)