SAT Problem Solving and Data Analysis - Percentages HARD

Front

What is a percentage?

Back

A percentage is a fraction expressed as a part of 100. It represents how much of one quantity is present in relation to another.

Front

How do you calculate a percentage of a number?

Back

To calculate a percentage of a number, multiply the number by the percentage (in decimal form). For example, to find 20% of 50, calculate 50 * 0.20 = 10.

Front

What is the formula for finding the percentage increase?

Back

Percentage Increase = ((New Value - Original Value) / Original Value) * 100.

Front

What is the formula for finding the percentage decrease?

Back

Percentage Decrease = ((Original Value - New Value) / Original Value) * 100.

Front

If a shirt originally costs $40 and is on sale for $30, what is the percentage decrease in price?

Back

Percentage Decrease = ((40 - 30) / 40) * 100 = 25%.

Front

What does it mean if a quantity increases by 15%?

Back

It means the new quantity is 115% of the original quantity.

Front

How do you convert a percentage to a decimal?

Back

To convert a percentage to a decimal, divide by 100. For example, 25% = 25/100 = 0.25.

Front

What is the relationship between fractions and percentages?

Back

Fractions can be converted to percentages by multiplying by 100. For example, 1/4 = 0.25 = 25%.

Front

If 60% of a class of 30 students passed a test, how many students passed?

Back

Number of students passed = 30 * 0.60 = 18 students.

Front

What is a common mistake when calculating percentages?

Back

A common mistake is not converting the percentage to a decimal before performing calculations.