7-7 Percent of a Numberand

7-8 The percent Proportion

Turn and Talk

• What’s your favorite subject in school?

Favorite Subject

• A graph at the right shows the results of a survey in which 1,016 people were asked their favorite subject.

• About how many of them said language?

• How did you estimate?Scie

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Favorite Subject

• Suppose you pass 50 people at the mall, do you think more or less than 25 of them would choose PE as their favorite subject? Explain

Scienc

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Using PROPORTIONS!!!

• The graphic shows that 12% of the 1,016 students chose science as their favorite subject.

• How many of the students chose science?Scie

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Using EQUATIONS!!!

• The graphic shows that 12% of the 1,016 students chose science as their favorite subject.

• How many of the students chose science?Scie

nce

Mat

h

Histor

y

Lang

uagePE

Example 1

• Out of 1,423 adults surveyed, 30% said they knew the name of their mail carrier. How many of the people surveyed knew their mail carrier’s name?

• Use a proportion and equation (T-chart)

Example 2

• What number is 140% of 32?

Example 3

• Find 75% of $800

Example 4

• What number is 120% of 24?

Example 5

• Find 25% of $600

Your TurnWork one with a proportion and one

with an equation

A. Fifty percent of 140 is what number?

B. Find 37.5% of 64

Example 6

• What percent of $15 is $9?

Example 7 With a partner-set up the proportion on each problemA. What percent of 6 is 3?

B. What number is 50% of 6?

C. 3 is 50% of what number?

Example 8

• What number is 40% of 120?

Example 9

• 18 is 25% of what number?

Example 10

• What percent of 24 is 18?

Example 11

• What number is 30% of 150?

Example 12

• 12 is 80% of what number?

Your Turn

a. What number is 5% of 60?

b. 80 is 75% of what number?

Journal

• Which method do you prefer?

• Why?

Homework

• p 320: 3, 10-18 even, 22 (7 problems)

• p 325: 8-18 even, 21, 24 (8 problems)