Question

Apply Math Models You have 20 quarters. You

find 40% more quarters in your room. Then you go
shopping and spend 50% of the total number of
quarters.
a. Write an expression that represents the
total number of quarters you take with
you when you go shopping.
b. How much money do you have left?
18. H
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Answer 1

a. Let Q be the total number of quarters you take with you when you go shopping. The total number of quarters you have is 20, and you find 40% more quarters in your room, which is an additional 0.4 * 20 = <<0.420=8>>8 quarters. Therefore, the total number of quarters you have after finding more quarters in your room is 20 + 8 = <<20+8=28>>28 quarters. When you go shopping, you spend 50% of the total number of quarters, which is 0.5 * 28 = <<0.528=14>>14 quarters. Therefore, the total number of quarters you take with you when you go shopping is 28 - 14 = <<28-14=14>>14 quarters. This can be represented by the expression Q = 28 - 0.5 * 28.

b. If you have 14 quarters with you when you go shopping, and you spend 50% of the total number of quarters, then you have 0.5 * 14 = <<0.514=7>>7 quarters left. Since each quarter is worth $0.25, you have 7 * 0.25 = $<<70.25=1.75>>1.75 left. Answer: \boxed{1.75}.