Exercise 3 Page 124

Let's start by recalling that the percent proportion is a proportion that sets the ratio of a part of a whole equal to the ratio of a percent out of 100. part/whole=percent/100 We want to find the number of which 90.5 % is 62, which means that we want to find the whole. Let w represent the whole. 62/w=90.5/100 Now we can solve the proportion we got for w. Let's do this by using the fact that the cross products of any proportion are equal.

62/w=90.5/100

CrossMult

Cross multiply

62* 100= w * 90.5

Multiply

Multiply

6200=90.5w

Finally, we will use the Division Property of Equality to get the value of w.

6200=90.5w

DivEqn

.LHS /90.5.=.RHS /90.5.

6200/90.5=90.5w/90.5

CancelCommonFac

Cancel out common factors

6200/90.5=90.5w/90.5

SimpQuot

Simplify quotient

6200/90.5 = w

CalcQuot

Calculate quotient

68.508287... = w

RoundDec

Round to 1 decimal place(s)

68.5 ≈ w

RearrangeEqn

Rearrange equation

w ≈ 68.5

We got that w≈ 68.5 is a solution to the proportion. This means that 62 is 90.5 % of about 68.5.