Exercise 14 Page 273

Let x be number of which 75 % is 34. Write and solve a percent proportion using x.

Proportion: 3/4x= 75100
Solution: x=1

Practice makes perfect

We are told that 75 % of some number gives 34. Let x be this number.

We can write a percent proportion using x. 34/x=75/100 We will solve this equation using the Cross Product Property. Let's do it!

34/x=75/100

Cross multiply

3/4 * 100 = 75 * x

a/c* b = a* b/c

3* 100/4 = 75 * x

300/4 = 75x

Rearrange equation

75x=300/4

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Solve for x

Calculate quotient

75x = 75

.LHS /75.=.RHS /75.

75x/75 = 75/75

Calculate quotient

75x/75=1

Simplify quotient

x=1

We have that 34 is 75 % of 1.

1 Fractions, Decimals and Percents p.273

2 The Percent Proportion p.273

3 The Percent Equation p.274

4 Percents of Increase and Decrease p.274

5 Discounts and Markups p.275

6 Simple Interest p.275

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