Algebra 1 : Percent of Change
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Example Question #131 : Percent Of Change
Last week, a case of water cost $4.00. This week, it is on sale for $3.00 a case. Find the percent decrease.
To find the percent decrease, we will use the following formula:
Example Question #23 : How To Find The Percent Of Decrease
Yesterday, chicken cost $4 a pound. Today, it costs $3.50 a pound. Find the percent decrease.
To find the percent decrease, we will use the following formula:
Example Question #24 : How To Find The Percent Of Decrease
Last week, a shirt cost $25. This week, it is on sale for $10. Find the percent decrease.
To find the percent decrease, we use the following formula:
Therefore, the percent decrease of the shirt is 60%.
Example Question #25 : How To Find The Percent Of Decrease
A tennis player won 25 of her 35 matches in the fall season. In the spring season, she won 23 of her 35 matches. What was the tennis player's percent change in the number of games she won from fall to spring?
In this question, it is important to not be confused by the total amount of games number. Since the number of games is the same, you can just take the new amount of wins subtracted by the old amount of wins then divide by the old amount and multiply by 100.
The amount of games the tennis player won decreased by 8% from the fall season to the spring season.
Example Question #26 : How To Find The Percent Of Decrease
Your weekly allowance went from $40 to $30 a week. Find the percent decrease in your allowance.
To find percent decrease, we use the following formula:
Using the information given, we know the following:
so we can substitute these values into the formula. We get
Therefore, the percent decrease in your allowance is 
Example Question #27 : How To Find The Percent Of Decrease
In 2013, a water tower contained 950,000 gallons. By 2014, the tower only contained 860,000 gallons of water. What was the percentage change in the amount of water that the tower contained? (Round to one decimal place)
Use the formula new amount subtracted by old amount then divided by the old amount and multiplied by 100. The new amount in this case is 860,000 and the old amount is 950,000.
The amount of water in the tower decreased by 9.5%
Example Question #28 : How To Find The Percent Of Decrease
When performing a Google search for "Lions" the amount of search results are 257 million. After refining the search to "African Lions" the amount of search results is 6.7 million. What is the percentage change by going from a search for "Lions" to "African Lions"? (Round the answer to one decimal place)
The percent change formula new amount subtracted by old amount then divided by old amount and multiplied by 100 should be used for this problem. The new amount is 6.7 million and the old amount is 257 million. It is not necessary to use the expanded numbers 6,700,000 or 257,000,000 to work out the problem but it will also work.
By refining the search, the amount of search results fell by 97.4%
Example Question #29 : How To Find The Percent Of Decrease
A closet contains 250 shoes. During spring cleaning, the owner decides to donate away 50 of those shoes. What is the percentage change in the amount of shoes the person owns?
Use the percentage change formula new amount subtracted by old amount then divided by old amount and multiplied by 100. It is important in this question to realize what the new and old amount are. The old amount is 250 shoes. The new amount is 250 less the 50 shoes so 200. The formula should be
The amount of shoes owned decreased by 20%.
Example Question #31 : How To Find The Percent Of Decrease
Simplify the expression
What is the exponent of 
Apply the properties of exponents as follows:
5 is the correct choice.
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