Answer:
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"
Step-by-step 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"