Basic, algebraic percent questions are common on the ACT test.  They range in difficulty from simple & straightforward to confusing & challenging. One question might ask you to find out what percent is a number out of another number.   Others might include multiple percents in the same problem.  Most percent questions on the ACT can be solved using the same, three-part formula.  percent = part/whole x 100

Percent means 100th.  A percent is 1/100th of something. You can change a percent into a decimal by adding a decimal point two places to the left and drop the percent sign.   15%= .15    You can change it to a fraction by writing it over 100.  15/100

The most common types of percent questions are

• Percent Taken Off
• Percent Change
• Combined Percents

Percent Taken Off- The question will either give you a whole and ask you to find a new value when a percent is taken off.  For example, a purse at $80 is discounted 10%.  What is the price of the discounted purse?   First, subtract the percent from 100 (equals 90).  Then, convert 90% into a decimal->( .90)  Last, multiply the decimal by the whole amount .90 x 80 =72.  Your answer  is $72.00.

Percent Change- This question will give you a value and a new value, and ask you to find the percent increase or decrease between those values.  Using the same example above, the question might ask if a purse that cost $80.00 was discounted to $72.00, what percent was the discount?  The answer is 10%

Combined Percents-  This question will give you a whole value, then take a percent off of the whole value twice consecutively.  Here’s an example:  A purse retailed for $80.00 on Monday. It was discounted 10% one day, and 20% the next day.   What is the total percent discount applied to the purse?  The answer is a $24.00-discount because the cost of the purse was $56.00 after the combined 30% discount.