1. 6-4 Percent of a Number Do Now Multiply. 1. 0.05  20 2. 0.32  15
Course 2
6-4
Percent of a Number
Do Now
Multiply.
 20
 15
 25
 18
 76 1
4.8
1.5
13.5
25.84
Hwk: 54

2. 6-4 Percent of a Number Learn to find the percent of a number.
Course 2
6-4
Percent of a Number
Learn to find the percent of a number.
M7A2.a Given a problem, define a variable, write an equation, solve the equation, and interpret the solution;
M7A2.b Use the addition and multiplication properties of equality to solve one- and two-step linear equations;

3. 6-4 Percent of a Number Part 67 n = Whole 100 90
Course 2
6-4
Percent of a Number
The human body is made up mostly of water. In fact, about 67% of a person’s total (100%) body weight is water. If Cameron weighs 90 pounds, about how much of his weight is water?
Part 67 = n
100 90
Whole

4. Additional Example 1A: Using Proportions to Find Percents of Numbers
Course 2
6-4
Percent of a Number
Additional Example 1A: Using Proportions to Find Percents of Numbers
Find the percent of each number.
30% of 50 30
100 n 50 =
30 · 50 = 100 · n
1,500 = 100n
1,500
100n =
100
100
15 = n
30% of 50 is 15.

5. Course 2
6-4
Percent of a Number
When solving a problem with a percent greater than 100%, the part will be greater than the whole.
Helpful Hint

6. Additional Example 1B: Using Proportions to Find Percents of Numbers
Course 2
6-4
Percent of a Number
Additional Example 1B: Using Proportions to Find Percents of Numbers
Find the percent of each number.
200% of 24
200
100 n 24 =
200 · 24 = 100 · n
4,800 = 100n
4,800
100n =
100
100
48 = n
200% of 24 is 48.

7. 6-4 Percent of a Number Check It Out: Example 1A
Course 2
6-4
Percent of a Number
Check It Out: Example 1A
Find the percent of each number.
40% of 40 40
100 n 40 =
40 · 40 = 100 · n
1,600 = 100n
1,600
100n =
100
100
16 = n
40% of 40 is 16.

8. 6-4 Percent of a Number Check It Out: Example 1B
Course 2
6-4
Percent of a Number
Check It Out: Example 1B
Find the percent of each number.
150% of 64
150
100 n 64 =
150 · 64 = 100 · n
9,600 = 100n
9,600
100n =
100
100
96 = n
150% of 64 is 96.

9. Course 2
6-4
Percent of a Number
Additional Example 2A: Using Decimal Equivalents to Find Percents of Numbers
Find the percent of the number. Check whether your answer is reasonable.
9% of 80
9% of 80 = 0.09 · 80
= 7.2

10. Course 2
6-4
Percent of a Number
Additional Example 2B: Using Decimal Equivalents to Find Percents of Numbers
Find the percent of the number.
3% of 12
3% of 12 = 0.03 · 12
= 0.36

11. 6-4 Percent of a Number Check It Out: Example 2A
Course 2
6-4
Percent of a Number
Check It Out: Example 2A
Find the percent of the number. Check whether your answer is reasonable.
21% of 40
21% of 40 = 0.21 · 40
= 8.4

12. 6-4 Percent of a Number Check It Out: Example 2B
Course 2
6-4
Percent of a Number
Check It Out: Example 2B
Find the percent of the number.
6% of 18
6% of 18 = 0.06 · 18
= 1.08

13. Additional Example 3: Geography Application
Course 2
6-4
Percent of a Number
Additional Example 3: Geography Application
The estimated world population in 2001 was 6,157 million. About 40% of the people were 19 or younger. What was the approximate number of people 19 or younger, to the nearest million?
Find 40% of 6,157 million.
0.40 · 6,157
2,462.8

14. 6-4 Percent of a Number Check It Out: Example 3
Course 2
6-4
Percent of a Number
Check It Out: Example 3
The estimated world population in 2001 was 6,157 million. About 60% of the people were above 19 years of age. What was the approximate number of people 19 or older,
to the nearest million?
Find 60% of 6,157 million.
0.60 · 6,157
3,694.2
The number of people 19 or older was about 3,694 million.

15. Insert Lesson Title Here
Course 2
6-4
Percent of a Number
Insert Lesson Title Here
You Try
Find the percent of each number.
1. 25% of 8
2. 40% of 110
Find the percent of each number. Check whether your answer is reasonable.
3. 150% of 96
4. 0.3% of 120
5. Whitmer Middle School has 850 students. If 42% of the students bought lunch on Monday, how many student bought lunch on Monday? 2 44
144
0.36
357