Chapter 7.2, Problem 29E

To determine

To calculate: The number whose is $60\%\text{ is 3}y$ .

Answer to Problem 29E

  $\text{5}y\text{ is the number whose 60\% is 3}y\text{.}$

Explanation of Solution

Given information:

the information given in the question:

  $60\%\text{ of the number is 3}y$

Concept used:

  $\begin{array}{l}\text{Represent }"a\text{ is }p\text{ percent of }b\text{" using the proportion}\\ \frac{a}{b}=\frac{p}{100}\\ \text{where }a\text{ is a part of the base }b\text{ and }p\text{\%,or }\frac{p}{100},\text{ is the percent}\text{.}\end{array}$

Calculation:

As per the problem

  $60\%\text{ of the number is 3}y$

Write the proportion

  $\frac{a}{b}=\frac{p}{100}$

Substitute $\text{3}y\text{ for }a\text{ and 60 for }p$ ,

  $\frac{3y}{b}=\frac{60}{100}$

Use cross product property

  $3y\cdot 100=60\cdot b$

Multiply

  $300y=60b$

Divide each side by $\text{60}$ and simplify

  $\text{5}y=b$ .

Hence,

  $\text{5}y\text{ is the number whose 60\% is 3}y\text{.}$