1. Finding a Percent of a Number
COURSE 2 LESSON 6-4
Finding a Percent of a Number
Find each answer.
a. 15% of 40
Method 1   Write 15% as a fraction and multiply.
Write the percent as a fraction in simplest form.
15% = = 15
100 3 20 3 20
• 40 = 6
Multiply.
Method 2   Write 15% as a decimal and multiply.
Write the percent as a decimal.
15% = 0.15
0.15 • 40 = 6
Multiply.
6-4

2. Finding a Percent of a Number
COURSE 2 LESSON 6-4
Finding a Percent of a Number
(continued)
b. 80% of 460
Method 1   Write 80% as a fraction and multiply.
Write the percent as a fraction in simplest form.
80% = = 80
100 4 5 4 5
• 460 = 368
Multiply.
Method 2   Write 80% as a decimal and multiply.
Write the percent as a decimal.
80% = 0.80
0.80 • 460 = 368
Multiply.
6-4

3. Finding a Percent of a Number
COURSE 2 LESSON 6-4
Finding a Percent of a Number
There are 25 students in a class. 20% of them have green eyes. How many have green eyes?
Estimate  20% of • 25 or about 6 1 4
Change the percent to a decimal.
   20% = 0.2
0.2 • 25 = 5
Multiply.
Five students in the class have green eyes.
Check for Reasonableness  The answer 5 is close to the
estimate 6. The answer is reasonable.
6-4