Question

Question #75b7f

Answer 1

60 books were donated.

Explanation:

What we are looking for is:

48 is 80% of what?

In mathematics "is" means "`=`".

"Percent" or "%" means "out of 100" or "per 100", Therefore 80% can be written as `80/100`.

When dealing with percents the word "of" means "times" or "to multiply".

And we can call "what" `n`.

So putting this altogether gives:

`48 = 80/100 *xx n`

Solving for `n` gives:

`100/80 xx 48 = 100/80 xx 80/100 xx n`

`4800/80 = 8000/8000 x n`

`60 = n`

Answer 2

The count of donated books was 60

Explanation:

The symbol % is a unite of measurement worth `1/100`

So 80% `-> 80/100`

Let the total count of books donated be `x`
Given that the count sold is 48
Given that the percentage sold is 80%

`80/100xx x = 48`

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If you multiply `80/100" by " 100/80` you turn it into 1

So this is:

`80/100xx100/80 = (80xx100)/(100xx80) = (100xx80)/(100xx80) =100/100xx80/80 =1xx1`

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Multiply both sides by `100/80`

`1xxx= 4800/80 = 60`

`x=60`