2006 AMC 12B Problems/Problem 4

Problem

Mary is about to pay for five items at the grocery store. The prices of the items are $7.99$ , $4.99$ , $2.99$ , $1.99$ , and $0.99$ . Mary will pay with a twenty-dollar bill. Which of the following is closest to the percentage of the $20.00$ that she will receive in change?

$\text {(A) } 5 \qquad \text {(B) } 10 \qquad \text {(C) } 15 \qquad \text {(D) } 20 \qquad \text {(E) } 25$

Solution

The total price of the items is $(8-.01)+(5-.01)+(3-.01)+(2-.01)+(1-.01)=19-.05=18.95$

$20-18.95=1.05$

$\frac{1.05}{20}=.0525 \Rightarrow \text{(A)}$

Alternative Solution

We can round the prices to $8$ , $5$ , $3$ , $2$ , and $1$ .

So $20 - (8+5+3+2+1) = 1$

We can make an equation: $20* \frac{x}{100}=1$

If we simplify the equation to "x", we get $x=5$

2006 AMC 12B (Problems • Answer Key • Resources)
Preceded by Problem 3	Followed by Problem 5
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All AMC 12 Problems and Solutions

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2006 AMC 12B Problems/Problem 4

Contents

Problem

Solution

Alternative Solution

See also