Art of Problem Solving

1986 AJHSME Problems/Problem 15: Difference between revisions

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==Problem==
==Problem==


Sale prices at the Ajax Outlet Store are <math>50\% </math> below original prices.  On Saturdays an additional discount of <math>20\% </math> off the sale price is given.  What is the Saturday price of a coat whose original price is <math>\dollar 180</math>?
Sale prices at the Ajax Outlet Store are <math>50\% </math> below original prices.  On Saturdays an additional discount of <math>20\% </math> off the sale price is given.  What is the Saturday price of a coat whose original price is <math>\textdollar 180</math>?


<math>\text{(A)}</math> <dollar/><math>54</math>
<math>\text{(A)}</math> <math>\textdollar 54</math>


<math>\text{(B)}</math> <dollar/><math>72</math>
<math>\text{(B)}</math> <math>\textdollar 72</math>


<math>\text{(C)}</math> <dollar/><math>90</math>
<math>\text{(C)}</math> <math>\textdollar 90</math>


<math>\text{(D)}</math> <dollar/><math>108</math>
<math>\text{(D)}</math> <math>\textdollar 108</math>


<math>\text{(D)}</math> <dollar/><math>110</math>
<math>\text{(D)}</math> <math>\textdollar 110</math>


==Solution==
==Solution==

Revision as of 14:32, 9 November 2017

Problem

Sale prices at the Ajax Outlet Store are $50\%$ below original prices. On Saturdays an additional discount of $20\%$ off the sale price is given. What is the Saturday price of a coat whose original price is $\textdollar 180$?

$\text{(A)}$ $\textdollar 54$

$\text{(B)}$ $\textdollar 72$

$\text{(C)}$ $\textdollar 90$

$\text{(D)}$ $\textdollar 108$

$\text{(D)}$ $\textdollar 110$

Solution

First we need to do the first discount, which, at Ajax Outlet Store, would be there any day of the week. \begin{align*} 180 \times 50\% &= 180 \times \frac{1}{2} \\ &= 90 \\ \end{align*}

If we discount $20\%$, then $80 \%$ will be left, so after the second discount, we get \begin{align*} 90 \times 80\% &= 90 \times \frac{8}{10} \\ &= 9 \times 8 \\ &= 72 \\ \end{align*}

$\boxed{\text{B}}$

See Also

1986 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 14
Followed by
Problem 16
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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