# Question 47bec

Mar 31, 2017

35.7%

#### Explanation:

$\frac{0.25}{70} = 0.357 \ldots$

0.357xx100=35.7%

Mar 31, 2017

35 5/7% Exactly

If you use decimals you do not have a precise answer

~~35.71% to 2 decimal places $\leftarrow$ approximately

#### Explanation:

$\textcolor{b l u e}{\text{Very important facts about percentages}}$

Percent is just another fraction. The special thing about percent is that the bottom number (denominator) is fixed at 100.

The symbol % is like a unit of measurement but one where it is worth $\frac{1}{100}$

So as an example: 20%->20xx%->20xx1/100=20/100
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$\textcolor{b l u e}{\text{Answering the question}}$

Let the unknown value be $x$ then we have:

$\frac{25}{70} = \frac{x}{100}$

To 'get' $x$ on its own we need to 'get rid' of the 100 in $\frac{x}{100}$. We do this by changing into 1 because $1 \times x \text{ gives just } x$

Multiply both sides by 100

$\textcolor{g r e e n}{\frac{25}{70} \textcolor{red}{\times 100} \text{ "=" } \frac{x}{100} \textcolor{red}{\times 100}}$

$\textcolor{g r e e n}{\frac{5}{14} \textcolor{red}{\times 100} \text{ "=" } x \times \frac{\textcolor{red}{100}}{100}}$

but $\frac{100}{100}$ is the same as 1 giving:

$x = 35 \frac{5}{7}$

So we have:" "(35 5/7)/100" "=" "35 5/7xx1/100" "=" "35 5/7%#