2006 AMC 12B Problems/Problem 4

Revision as of 20:04, 26 July 2013 by Weegee13 (talk | contribs) (Solution)

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 $20 - (8+5+3+2+1) = 1$ $20* \frac{x}{100}=1$ By simplifying to "x", we get $\box{5}$ (Error compiling LaTeX. ! Missing number, treated as zero.)

See also

2006 AMC 12B (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AMC 12 Problems and Solutions

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