5.4 APPLICATIONS OF PERCENTI can find and estimate solutions to application problems involving percent and use different ways to represent a situation.

Finding Sales Tax

A video game costs $34.98. The sales tax rate is 5.5%. How much will you pay for the video game?

Find the sales tax A = 0.055(34.98) and round to the

nearest hundredth A ≈ 1.92 Add to the original cost $34.98 + $1.92 = $36.90 (the total cost)

Estimating a Tip

Use estimation to calculate a 15% tip for $34.50.

Round to the nearest dollar $35

Find 10% of the bill: 0.1(35) = $3.50 Find 5% of the bill. 5% is ½ of the 10%

amount $1.75

Add 10% amount and 5% amount to get $5.25

A 15% tip for $34.50 is about $5.25

Finding a Commission

Find the commission on a $300 sale, with a commission rate of 8.5%

A = 0.085(300) $25.50

Practice

Find the total earnings for a salesperson with a salary of $550 plus 4% commission on sales of $1,485.

total earnings = salary + commission 550 + 0.04(1485) 550 + 59.4 $609.40

Percent Error in Manufacturing A 625-g mass measures 625.18 g. What

is the percent error? Percent error = ∙ 100 Percent error = ∙ 100 Percent error = ∙ 100 = 0.0288% Round to nearest hundredth: 0.03%

Assignment

ODDS P.195 #9-27