Question

Marina wants to purchase a rosebush ford dollars at a garden store. She has a coupon good for

$5 off her purchase, and the store is having a 10% off sale.
Part A
Write two different, equivalent expressions for how much the rosebush will cost if the coupon.is
applied first and the 10% discount second.
Part B
Write an expression for how much the rosebush will cost if the 10% discount is applied first and
the coupon is applied second.
Part
Which order will save Marina more money? Explain your reasoning.

Answer 1

Part A: 0.9d - 4.5

Part B: 0.9d - 5

Part C: Order that will save Marina money is "discount applied first, then coupon"

Explanation:

Part A

The rosebush costs "d" dollars

Coupon = $5 OFF

Discount = 10%

We want to find cost of rosebush when COUPON APPLIED 1st and DISCOUNT APPLIED 2nd.

Cost = d

Coupon Applied Cost = (d - 5)

Discount Applied Cost = 10% off means 100 - 10 = 90% of the price remains, that is 90/100 = 0.9 times the price, so:

0.9(d - 5) = 0.9d - 4.5

Part B

When we apply 10% discount to the initial price of "d", we get 90% of the price remaining.

So, price would be:

Normal Price = d

Discount Price = 0.9d

Now, coupon applied of $5, we get:

0.9d - 5

Part C

We have two expressions, let the original price, d, be 100, so

Part A price would be 0.9d - 4.5 = 0.9(100) - 4.5 = 85.5

Part B price would be 0.9d - 5 = 0.9(100) - 5 = 85

So, Marina will save up money going on the 2nd option.

Order that will save Marina money is "discount applied first, then coupon"