Question

write an equation for each problem. then solve. round to the nearest tenth if necessary.

1. 9 is what percent of 45?

$9 = n \times 45$
$\frac{9}{45} = \frac{45n}{45}$
$0.2$ or $20\\% = n$

1. what percent of 96 is 26?

$26 = n \times 96$
$\frac{26}{96} = \frac{96n}{96}$
$0.271$ or $27.1\\% = n$

1. what percent of 392 is 98?
2. 30 is what percent of 64?
3. 33% of what number is 1.45?
4. 84 is 75% of what number?

Explanation:

Problem 20:

Step1: Set up percent equation

Let $n$ = unknown percent.
$98 = n \times 392$

Step2: Isolate $n$ by division

$\frac{98}{392} = \frac{392n}{392}$

Step3: Calculate and convert to percent

$n = 0.25 = 25\%$

Problem 21:

Step1: Set up percent equation

Let $n$ = unknown percent.
$30 = n \times 64$

Step2: Isolate $n$ by division

$\frac{30}{64} = \frac{64n}{64}$

Step3: Calculate and round

$n \approx 0.469 = 46.9\%$

Problem 22:

Step1: Convert percent to decimal, set equation

$33\% = 0.33$, let $x$ = unknown number.
$0.33x = 1.45$

Step2: Isolate $x$ by division

$x = \frac{1.45}{0.33}$

Step3: Calculate and round

$x \approx 4.4$

Problem 23:

Step1: Convert percent to decimal, set equation

$75\% = 0.75$, let $x$ = unknown number.
$0.75x = 84$

Step2: Isolate $x$ by division

$x = \frac{84}{0.75}$

Step3: Calculate value

$x = 112$

Answer:

1. $25\%$
2. $46.9\%$
3. $4.4$
4. $112$