Question

Question #db6ff

Answer 1

`0.000665 = 6.65xx10^(-4)`

Explanation:

`color(blue)("Principle used")`

Consider the number 2. If you multiply by 1 you do not change its value. However, 1 comes in many forms. So you can change the way it looks without changing its true value

`color(green)([2color(red)(xx1)] -=[2color(red)(xx10/10)] =[20xx1/10]`

But `1/10` is the same as `10^(-1)`

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
`0.000665 -> 0.0065xx1/10`
`0.000665 -> 0.065xx1/10xx1/10`
`0.000665 -> 0.65xx1/10xx1/10xx1/10`
`0.000665 -> 6.5xx1/10xx1/10xx1/10xx1/10`

but `1/10xx1/10xx1/10xx1/10 = 1/(10^4) = 10^(-4)`

So `0.000665 = 6.65xx10^(-4)`