To find percent increase:
1) First,
find how much the increase was. Subtract the original number from the new number:
60 pairs - 50 pairs =
10
2)
Find the percent increase. Divide the increase (10) by the original number (50). Multiply the decimal you get by 100% to get the percentage.
![(10)/(50) * 100\% \\ = 0.2 * 100\%\\ = 20\%](https://img.qammunity.org/2019/formulas/mathematics/middle-school/ix85mzhripyzr6k19e9qhedecw2kvwln08.png)
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Answer: 20% increase