Percentages

Let's demonstrate this using two examples.

Example 1.

What is $1\over4$ of $20$?

Solution:

When we are asked to find a part ($1\over4$) of a whole ($20$), we need to multiply the part by the whole.

Therefore we get: $\frac{1}{4} \cdot 20 = \frac{20}{4} = 5$

Example 2.

A shirt cost $40$ Dollars and now it's on sale with a $20$ discount.

We are asked to calculate the price of the shirt after the price reduction.

Solution:

After the price reduction, the shirt's price is actually $80$ (before the reduction the price was $100$).

$80$ is actually $\frac{80}{100}= \frac{8}{10}= 0.8$.

To calculate $80$ of $40$, we perform a simple multiplication - $40\cdot0.8 = 32$.

In other words, the price of the shirt after the price reduction is $32$ shekels.