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Questions
\(\textbf{1)}\) Jessica collects rocks. She started the week with 20 rocks. Later in the week she traded 3 of her rocks to Steve for 12 of his rocks. She then sold 5 to her brother. After all of this, what is the percent of increase in Jessica’s rock collection? 
\(\textbf{2)}\) One day, a stock increases in value by 25%. The next day it decreases by 25%. By what percent did the value of the stock change after both days?
\(\textbf{3)}\) Harry wanted to buy a book that cost $20 last week. This week he came back and it cost $25. What was the percent change (magnitude and direction) in the price of the book? Show your work.
\(\textbf{4)}\) Harry waited on the $25 book. It was just too expensive for him. But after Christmas, he saw that it was on sale for $20. What was the percent change (magnitude and direction) in the price of the book? Show your work.
\(\textbf{5)}\) You should have gotten different percent rates for questions 3 and 4 even though the amount of change in dollars is the same. Explain why the percent rates are different.
\(\textbf{6)}\) The price of an hour of babysitting was $7.50 in 2000. In 2010, the price was $15. What was the percent change (magnitude and direction) in the price of the babysitting? Show your work.
\(\textbf{7)}\) A compass decreased in price from $40 to $10 in the last 5 years. What was the percent change (magnitude and direction) in the price of the compass? Show your work.
\(\textbf{8)}\) Sam has $100 in a stock. On Tuesday, the stock decreases 25% from the day before. Sam is unhappy with this. On Wednesday the stock increases 25% from the day before.Sam is happy again. Did Sam get all his money back?
See Related Pages\(\)
\(\bullet\text{ Converting Percents to Decimals}\)
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\(\bullet\text{ Converting Percents, Decimals and Fractions}\)
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\(\bullet\text{ Percent Problems}\)
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\(\bullet\text{ Percent Word Problems}\)
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