Question

If $400 is invested at the rate of 6% for one year, what will be the total value of the investment (the amount)?

Answer 1

`$424.00`

Explanation:

Sowing you a slightly different approach with explanation of how we get there.

We end up with `color(red)((106)/100xx$400)`
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`color(blue)("This is how the final expression is derived")`

Percentage is just a fraction but a special one in that the bottom number (denominator) is always set at 100.

So, as a fraction, all of something is

`1xx" whatever it is"=>100/100xx" whatever it is"`

So in this case we have all of the $400 + a bit of the $400

`(100/100xx$400)+(6/100xx$400)`

Factoring out the $400 we have:

`$400(100/100+6/100) ->color(red)($400xx106/100)color(blue)( = $424)`
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Trick for non calculator

`$400xx106/100` is the same as `$400/100xx106 -> $4xx106=$424`