Percent Change & Error

Front

What is Percent Change?

Back

Percent Change is a way to express a change in value as a percentage of the original value. It is calculated using the formula: ((New Value - Original Value) / Original Value) x 100.

Front

How do you calculate Percent Decrease?

Back

Percent Decrease is calculated using the formula: ((Original Price - Sale Price) / Original Price) x 100.

Front

How do you calculate Percent Increase?

Back

Percent Increase is calculated using the formula: ((New Price - Original Price) / Original Price) x 100.

Front

What is the formula for Percent Error?

Back

Percent Error is calculated using the formula: (|Estimated Value - Actual Value| / Actual Value) x 100.

Front

If a shirt originally costs $36 and is on sale for $24, what is the percent decrease?

Back

33% decrease.

Front

If a microwave costs $96 and is marked up to $115.20, what is the percent increase?

Back

20% increase.

Front

In 1999, the price of fuel was $1.09 and in 2015 it was $1.89. What is the percent change?

Back

73% increase.

Front

A school's population increased from 1250 to 2000 students. What was the percent of increase?

Back

60% increase.

Front

You estimated sending 135 texts but actually sent 108. What was your percent error?

Back

20% error.

Front

What does a positive percent change indicate?

Back

A positive percent change indicates an increase in value.