Question

How do you convert 4/5 into a decimal and percent?

Answer 1

`color(blue)(4/5 -> 80% -> 80/100)`

`color(blue)(4/5-=8/10-=0.8)`

Explanation:

Decimal values are made up of:

`...+100's+10's+1's+" decimal point "+1/10color(white)("")^(ths)+1/100color(white)("")^(ths)+1/1000color(white)("")^(ths)+..." and so on."`
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`color(blue)("Considering "4/5" as a decimal")`

The denominator is 5 so if we can convert this to 10 we have our first decimal place of counting in tenths.

Multiply by 1 but in the form of `1=2/2` giving:

`4/5" "-=" "4/5xx1" "-=4/5xx2/2" " =" "(4xx2)/(5xx2)" " =" "8/10`

So `color(blue)(4/5-=8/10-=0.8)`

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`color(blue)("Considering "4/5" as a percentage")`

Percentage can be written in 2 ways.

Suppose we hade 60 percent. Then this can be written as

`60%" which is the same as "60/100`

So percentage is counting in `1/100color(white)("")^(ths)`

Multiply by 1 in the form of `1=2/2" and then by "1=10/10`

`4/5xx2/2xx10/10" " -=" "8/10xx10/10" "-=" "80/100`

So `color(blue)(4/5 -> 80% -> 80/100)`