Difference between revisions of "1990 AJHSME Problems/Problem 13"

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==Solution==
 
==Solution==
  
After the first ounce, there are <math>3.5</math> ounces left.  Thus, it is required to pay for <math>3</math> ounces and then the extra half.
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After the first ounce, there are <math>3.5</math> ounces left.  Since each additional ounce or fraction of an ounce adds <math>22</math> cents to the total cost, we need to add <math>4\times 22</math> to the cost for the first ounce.
  
The total price is <math>30+3.5\times 22=107</math> cents, which is choice <math>\boxed{\text{B}}</math>. The answer key is wrong, it says <math>C</math> when the answer is <math>\boxed{\text{B}}</math>
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So, the total price is <math>30+4\times 22=118</math> cents. The answer is choice <math>\boxed{\textbf{(C)}~\mathbf{1.18}~\textbf{dollars}}</math>.
  
 
==See Also==
 
==See Also==

Latest revision as of 17:01, 8 August 2018

Problem

One proposal for new postage rates for a letter was $30$ cents for the first ounce and $22$ cents for each additional ounce (or fraction of an ounce). The postage for a letter weighing $4.5$ ounces was

$\text{(A)}\ \text{96 cents} \qquad \text{(B)}\ \text{1.07 dollars} \qquad \text{(C)}\ \text{1.18 dollars} \qquad \text{(D)}\ \text{1.20 dollars} \qquad \text{(E)}\ \text{1.40 dollars}$

Solution

After the first ounce, there are $3.5$ ounces left. Since each additional ounce or fraction of an ounce adds $22$ cents to the total cost, we need to add $4\times 22$ to the cost for the first ounce.

So, the total price is $30+4\times 22=118$ cents. The answer is choice $\boxed{\textbf{(C)}~\mathbf{1.18}~\textbf{dollars}}$.

See Also

1990 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 12
Followed by
Problem 14
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 AJHSME/AMC 8 Problems and Solutions

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