Flexi answers - What is 80% of 15? (2024)

Flexi Says:

Apercent is a ratio that describes a quantity out of 100. A percent is also a part of a whole. Finding the percent of a number is the part of a number that is equivalent to the percent.

Steps to find the percentage of a number - Method 1

Let's, find 80% of 15 using proportion.

First, write the percent as a fraction. 80% is also equal to 80 out of 100.

@$$\begin{align*}80\%=\frac{80}{100}\end{align*}@$$

Next, write a proportion to find the equivalent fraction of 80% of 15. The second fraction is the unknown quantity, represented by@$\begin{align*}x,\end{align*}@$ over the whole, 15.

@$$\begin{align*}\frac{80}{100}=\frac{x}{15}\end{align*}@$$

Now, cross-multiply to find the cross-product. To cross-multiply, multiply thenumerator of one fraction with the denominator of the other fraction. The products should be equal.

@$$\begin{align*}80(15)=100x\end{align*}@$$

Finally, simplify the equation to solve for @$\begin{align*}x.\end{align*}@$ Multiply 80 by 15 and divide both sides by 100.

@$$\begin{align*}80(15)&=100x\\[6pt]\frac{1200}{100}&=\frac{100x}{100}\\[6pt]12&=x\end{align*}@$$

Hence, 80% of 15 is 12.

Steps to find the percentage of a number - Method 2

Another strategy includes the use of keywords and multiplication. Let's re-examine the problem:

Determine 80% of 15.

First, look for keywords that suggest an operation. The word "of" tells you to multiply 15 by 80%.

To multiply 15 by 80% we need to convert the percentage into decimal.

@$$\begin{align*}80\%=0.8\end{align*}@$$

Then, write an equation to find the unknown number, @$\begin{align*}x.\end{align*}@$

@$$\begin{align*}x=15\times 0.8\end{align*}@$$

Finally, solve for @$\begin{align*}x\end{align*}@$ by multiplying 15 by 0.8.

@$$\begin{align*}x=15\times 0.8=12\end{align*}@$$ The answer is the same. 80% of 15 is 12.

Steps to find the percentage of a number - Method 3

The relationship@$\begin{align*}\text{percent} = \frac{\text{part}}{\text{whole}}\end{align*}@$ can be used to find the part value using the percentage and the whole provided to us. By multiplying the whole by the other side you get the following equation:@$$\begin{align*}\text{percent} \cdot \text{whole}= \text{part}\end{align*}@$$

Step 1: Divide the percentage by 100.

Step 2: Multiply the result by the whole.

For example, find 80% of 15.

Part = ?

Whole = 15.

Percent = @$\begin{align*}80\% \rightarrow \frac{80}{100}.\end{align*}@$

@$$\begin{align*}\text{Percent} \times \text{Whole}& = \text{Part} \\\frac{80}{100} \times 15 & = \text{Part} \\[3pt]0.8 \times 15 & = \text{Part} \\[6pt]12 & = \text{Part}\end{align*}@$$

∴ 80% of 15 is 12.

To learn more about percentages, click here!