While shopping, Dawn finds a backpack that she likes on the sale rack. Its original price is $60, but everything on the rack comes with a 30% discount. Dawn also has a coupon for 15% off of
her total purchase.
Dawn says, "Thirty percent and fifteen percent make forty-five percent and 45% of $60 is $33,
so it will cost $33."
Is Dawn correct? Explain why or why not. Be sure to support your reasoning with a
mathematical model.

No. Because 33 $ is the money deducted from the 60 $. Dawn bought everything for less than 60 $.

So, if Dawn purchases everything on the rack with a 30% discount and 15% coupon the total will indeed make 45%.

We have to take 100% - 45%= 55% to know the reduction number. Let's proceed to the calculations now.

100%= 60 $

1%=60/100

55%= 60/100 × 55 = 33 $

Now NOTE; 33 $ is the money reduced from the 60 $. So, logically, 33 $ isn't the amount which Dawn purchased the whole rack.

To find the amount at which she purchased everything, we need to do,

60 $ - 33 $ = 27 $

your answer would be 12