How do you write 7,930,000,000 in scientific notation?

1 Answer
Feb 16, 2016

Answer:

#=7.93 xx10^9#

Explanation:

The number that has the biggest impact if it is the one that is changed. It is called #color(blue)(" 'the most significant figure'")#.
It is the 7 as it is counting in the biggest units.

I say the next bit the way I do to avoid some classic mistakes that occur.

Keeping the decimal place where it is, 'slid' the number 9 places to the right so that you end up with:

#7.930# Although you have the same digits their value, written this way, has changed. So we need to convert them back to the original value.

We have reduced its value by a factor #10^9# so we need to increase it by the same size of factor:

#7930000000= (7930000000)/(color(brown)(10^9))xxcolor(brown)(10^9)#

#=7.93 xx10^9#
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In principle we have multiplied the original value by#" "color(brown)( 1 )" "#but in the form of #color(brown)(10^9/10^9)#