ACT Math : How to find the percent of decrease
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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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