Whta is 40% of 50?

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Answer 1 · 2018-05-30T14:15:08

20

There are two ways of writing percentage and they both mean EXACTLY THE SAME THING.

Method 1 $40%$

Method 2 $40/100$

Note that $40/100$ is the same thing as $40xx1/100$

The fraction format is special in that the bottom number is always fixed at 100. So, if these mean 'exactly' the same thing we have:

$40color(white)("ddd")%$
$40 color(white)("d")obrace(xx1/100)$

So the % symbol means $xx1/100$ including the multiply sign.
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In mathematics the word 'of' usually means multiply.

So we have: $color(white)("d")40%color(white)("d")" of "color(white)("d")50$

$color(white)("ddddddddd.")40/100color(white)("ddd")xxcolor(white)("dd")50$

$40/100xx50$

$40xx50/100 larr" you are allowed to move the 100 like this"$

$40xx1/2=20$

Answer 2 · 2018-05-30T14:19:40

$20$

$40%$ of $50$ is,

$40/100 * 50 = 20$

Another way is by decimals.

$0.4 * 50 = 20$

A trick that you could use:

$40 %$ of $50$ means

$40 * 50$ which is $2000$ and obviously it needs to be lower than $50$ because of the $40 %$ so you remove the two zeros and get $20$ .