Difference between revisions of "2019 AMC 8 Problems/Problem 22"
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==Solution 1== | ==Solution 1== | ||
| − | Suppose the amount of discount is <math>x. That means < | + | Suppose the amount of discount is <math>x</math>. That means <math>(1-x)(1+x)</math>=0.84x<math>; so </math>1-x^{2}=0.84<math>, and </math>(x^{2})=0.16<math>, obtaining </math>x=0.4$. |
==See Also== | ==See Also== | ||
Revision as of 19:23, 20 November 2019
Problem 22
A store increased the original price of a shirt by a certain percent and then decreased the new
price by the same amount. Given that the resulting price was 84% of the original price, by what
percent was the price increased and decreased?
Solution 1
Suppose the amount of discount is 
. That means 
=0.84x
1-x^{2}=0.84
(x^{2})=0.16
x=0.4$.
See Also
| 2019 AMC 8 (Problems • Answer Key • Resources) | ||
| Preceded by Problem 6 |
Followed by Problem 23 | |
| 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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