Exercise 4 Page 257

Let x represent the unknown number. Write and solve a percent equation using x.

56.25

Practice makes perfect

We know that 32 % of a number is 18. Let x be this unknown number.

We can write this relationship as a percent equation using x. 32 % * x=18 We will solve this equation using the Multiplication and Division Property of Equality. Let's do it!

32 % * x=18

a %=a/100

32/100 * x=18

a/c* b = a* b/c

32x/100= 18

LHS * 100=RHS* 100

32x/100* 100 =18 * 100

a/100* 100 = a

32x = 18* 100

32x=1800

Next, we will use the Division Property of Equality to simplify the equation even further.

32x=1800

.LHS /32.=.RHS /32.

32x/32=1800/32

Cancel out common factors

32x/32=1800/32

Simplify quotient

x=1800/32

Calculate quotient

x=56.25

We have that 18 is 32 % of 56.25.

Try It p.254-255

Self-Assessment for Concept & Skills p.255

Self-Assessment for Problem Solving p.256

Review & Refresh p.257

Concept, Skills, & Problem Solving p.257-258

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