Question #db6ff

1 Answer
Jan 19, 2017

#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)#