ACT Math : Percent of Change
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Example Questions
Example Question #11 : How To Find The Percent Of Increase
What is the percent increase from 
To find percent change, subtract the "old" amount from the "new" amount, then divide the result by the "old" amount. The result is a percent increase if positive and a percent decrease if negative.
Example Question #12 : How To Find The Percent Of Increase
A fundraiser for a local charity raised $28,000 in donations last year. The fundraiser’s goal for this year is to exceed last year’s donations by 15%. So far, they have raised $31,000. How much more money must the fundraiser raise to reach their goal?
$5500
$3200
$4200
$1500
$1200
$1200
First, let's calculate the value of this year's expected goal. Start by calculating 15 percent of last year's goal. Do this by converting 15 percent to a decimal by moving the decimal point two spaces to the left, and then multiplying this number by last year's goal.
Now, we can add this value to last year's goal to obtain the expected goal for this year's fundraiser.
Since $31,000 has been raised so far, the amount remaining is as follows:
Example Question #1 : How To Find The Percent Of Decrease
What is the percentage decrease from 2.4 gal. to 3.5 qts.?
64.53
63.54
112.53
33.45
63.54
Find a common unit – in this case it is ounces. The decrease is from 307.2 oz. to 195.2 oz. (128 oz x 2.4 gal. – 32 oz. x 3.5 qts.) 307.2 oz. – 112 oz. = 195.2 oz. Then, 195.2/307.2 = 63.54 %
Example Question #51 : Percentage
The regular price for a sweater in October is $80. In November, the store holds a Thanksgiving sale, and the price of the sweater is reduced by 7%. In December, the store holds a Christmas sale, and the November price of the sweater is reduced by an additional 6%. At the end of December, Jim purchases the sweater. By what percent did the price of the sweater decrease from October to December?
7.2%
12.6%
11%
8.4%
21%
12.6%
In October, the sweater cost $80. In November, it was reduced by 7%. 7% of $80 is $5.60 (0.07 x 80). Thus, the new price of the sweater is $80-$5.60, which is $74.40. In December, the sweater's price is reduced by an additional 6%. 6% of $74.40 is $4.46 (0.06 x 74.40). Thus, the December price for the sweater is $74.40-$4.46, which equals $69.94. To find the percent change, we take the change ($80-$69.94=$10.06) and divide by the initial price ($80). We then multiply that quotient by 100 to get 12.6%.
Example Question #3 : How To Find The Percent Of Decrease
A local appliance store puts a washing machine that usually sells for $200 on sale for $150. What is the percent discount?
10%
None of the answers are correct
50%
35%
25%
25%
% Discount = Amount of Discount ÷ Original Amount
% Discount = (Old Price – New Price) ÷ Original Amount
For this problem we have (200 – 150) ÷ 200 = 0.25 or 25% discount
Example Question #4 : How To Find The Percent Of Decrease
A company’s annual sales are as follows:
What is the percentage decrease in annual income from 
2010–2011:
% Decrease = (2010 Income – 2011 Income) / 2010 Income
= (100000 – 94000) / 100000 = 6000 / 100000 = 0.06 = 6%
2011–2012:
% Decrease = (2011 Income – 2012 Income) / 2011 Income
= (94000–93000) / 94000 = 1000 / 94000 = .01 = 1%
Example Question #5 : How To Find The Percent Of Decrease
In 2014, a basketball team won 
If the team won 
Step 1: Find 
Step 2: Subtract from
Example Question #6 : How To Find The Percent Of Decrease
If a new television cost 
First, calculate the amount of profit that will need to be made to earn a 
This means that it is a 
Example Question #7 : How To Find The Percent Of Decrease
A person who was originally 
The formula for percentage change is represented as:
Since the person has lost 
Since we are looking for the percentage of decrease, we can represent this as a positive number. (To decrease by a positive amount is to have a negative percentage change, absolutely speaking.) Thus, our answer is 
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