Calculating Percent Changes and Errors

What is the main concept discussed in the introduction?

• Understanding the value of money

• Converting absolute changes to percentage changes

• Calculating absolute changes in amounts

• Learning about fractions

If the new amount is less than the original amount, what type of percent change is it?

• Percent error

• Percent decrease

• Percent increase

• No change

In Example 1, how many hours were spent online on Sunday?

• 2 hours

• 4 hours

• 4.5 hours

• 5 hours

What is the percent increase in time spent online from Saturday to Sunday in Example 1?

• 100%

• 125%

• 175%

• 150%

In Example 2, how many home runs were there in 2012?

• 20

• 28

• 30

• 25

What is the percent decrease in home runs from 2012 to 2013 in Example 2?

• 28.6%

• 30.2%

• 26.8%

• 25.6%

In Example 3, what was the estimated length of the classroom?

• 21 feet

• 15 feet

• 16 feet

• 20 feet

What is the actual length of the classroom in Example 3?

• 15 feet

• 16 feet

• 20 feet

• 21 feet

How do you calculate percent error?

• Actual amount divided by estimated amount

• Amount of error divided by actual amount

• Estimated amount divided by actual amount

• Amount of error divided by estimated amount

What is the percent error in estimating the classroom length in Example 3?

• 25.8%

• 22.8%

• 24.8%

• 23.8%