dolphin
Get Started

SAT Math skill page

SAT Percent Change Practice

Set percent change against the original amount, not the new amount.

Practice percent change in Dolphin SATPractice questions
10-16 min practice time3 questions on pageProblem Solving and Data Analysis
Practice time10-16 min
Question bank3 questions
Best forProblem Solving and Data Analysis

What this tests

What to know for this SAT skill

Dolphin question bank

Practice your skill

Question 1 of 3Easy
A $40 item is discounted by 25%. What is the sale price?
  1. $10
  2. $25
  3. $30
  4. $35
Show answer and solution
Correct answerC. $30

Solution walkthrough

  1. 25% of 40 is 10, so the discounted price is 40 - 10 = 30.
Question 2 of 3Medium
A value increases from 80 to 100. What is the percent increase?
  1. 20%
  2. 25%
  3. 80%
  4. 125%
Show answer and solution
Correct answerB. 25%

Solution walkthrough

  1. The increase is 20, and 20/80 = 0.25 = 25%.
Question 3 of 3Hard
After a 20% increase, a price is $72. What was the original price?
  1. $54
  2. $57.60
  3. $60
  4. $90
Show answer and solution
Correct answerC. $60

Solution walkthrough

  1. The final price is 120% of the original.
  2. 72 / 1.2 = 60.

Avoid these traps

Common mistakes on this skill

Dividing by the new value

Percent change uses the original value as the denominator.

Using the percent itself as the multiplier

A p percent increase uses 1 + p/100; a decrease uses 1 - p/100.

Study plan

How to practice this skill in Dolphin

  1. Label the original and new values before calculating.
  2. Compute change divided by the original value, or use the appropriate multiplier.
  3. Check that the direction and approximate size of the result match the situation.
Practice percent change in Dolphin SAT

Related practice

Build the surrounding skills

SAT Math skill hubSAT Reading and Writing skill hubDolphin SAT study guidesSAT score guides by college

Skill cluster

Keep practicing SAT Math

SAT Math skill hubSAT Linear Equations PracticeSAT Systems of Equations PracticeSAT Linear Functions PracticeSAT Quadratic Equations PracticeSAT Percentages PracticeSAT Ratios and Proportions PracticeSAT Probability PracticeSAT Geometry PracticeSAT Right Triangles PracticeSAT Data Analysis PracticeSAT Circle Equations PracticeSAT Exponential Functions PracticeSAT Inequalities PracticeSAT Equivalent Expressions PracticeSAT Systems of Inequalities PracticeSAT Absolute Value Equations PracticeSAT Function Notation PracticeSAT Polynomials PracticeSAT Scatterplots PracticeSAT Mean and Median PracticeSAT Unit Conversions PracticeSAT Exponent Rules PracticeSAT Quadratic Word Problems PracticeSAT Systems Word Problems PracticeSAT Slope-Intercept Form PracticeSAT Area and Volume PracticeSAT Trigonometry PracticeSAT Rational Equations PracticeSAT Radical Equations PracticeSAT Conditional Probability PracticeSAT Sampling and Margin of Error PracticeSAT Statistical Claims PracticeSAT Reading and Writing Practice PagesDolphin SAT study guidesSAT score guides by college

FAQ

Questions about SAT Percent Change Practice

What is the percent-change formula?

It is (new value - original value) divided by the original value, multiplied by 100 percent.

Do equal percent increases and decreases cancel?

No. They use different base values; for example, up 20 percent and down 20 percent leaves 96 percent of the original.