Chapter 7, Problem 20CR

To determine

To find: The number.

Answer to Problem 20CR

  $51$is $60\%$of $85$ .

Explanation of Solution

Given information: $51$is $60\%$ of what number?

Calculation: Percent $(\%)$ means ‘out of $100$ ’ and when dealing with percents the word ‘of’ means ‘times or to multiply’.

Let, the number we are looking for is $x$ .

Hence, $60\%$ can be written as $\frac{60}{100}$ , and $60\%\text{ of }x$ can be written as $\frac{60}{100}\times x$ .

Therefore, $\text{51 is 60}\%\text{ of }x$ .

Let’s find the value of $x$ ,

  $\begin{array}{c}\frac{60}{100}\times x=51\\ x=\frac{51\times 100}{60}\\ x=\frac{51\times 5}{3}\\ x=17\times 5\\ x=85\end{array}$

Hence, $51$is $60\%$of $85$ .