Bell Ringer

Change the following fractions into decimals (round if you need to):

6/8

7/9

9/10

8/3

So what are we going to do today?

• Learn how to change between fractions, decimals, and percents.

• Learn how to handle ‘percent of’ problems

First of all, we need to know what EQUALS means:

• To say that two things are equal is to say that we can substitute one for the other.

• For example, we can say that 2 + 2 = 4. Both 4 and 2+2 mean the exact same thing.

• Remote control example…

We can express a number in different ways.

Fractions

Decimals

Percents

A Condensed Way to Understand Percent Conversion

Percent to Decimal:percentage > divide > decimal37 % = 37 / 100 = .37

Decimal to Percent:decimal > multiply > percent.37 = .37 x 100 = 37%

The ‘percentage of’ problem

What is 12% 0f

34?

What is 13% of 56?

What is 78% of

57?

To answer these questions

First: Change the percentage into a decimal

Second: Change the word ‘of’ into a X sign

Third: Workout

Example: What is 23% of 4523% = 0.23 and ‘of’ X

0.23 X 45 = 10.35

What do these words mean?

• Anytime you see ‘OUT OF,’ divide.• Anytime you see ‘OF,’ multiply.• Anytime you see ‘IS,’ put an equal sign.• Anytime you see ‘WHAT,’ put a variable.

Let’s try one:• 120 is what percent of 90?• All we are going to do is interpret the sentence.• 120 = x * 90– Note: x will need to be a percent (so when we get our

decimal, we need to multiply by 100 to get our answer).• Now, we just solve for x!• 120/90 = x• 1.333333 = x • But we want ‘x’ as a percent so we need to multiply

our decimal by 100.• So x = 133.33%

1. 25% of 32

2. 75% of 36

3. What percent of 74 is 222?

4. 150 is what percent of 80?

5. What number is 44% of 6?

Try these