Question #b9ad5

1 Answer
Oct 1, 2016

Have a look if you had this in mind:

Explanation:

I will try to "manipulate" your fraction to take advantage of scientific notation as:
#8400/(1.2xx10^7)=(84xx10^2)/(12xx10^6)=84/12*10^2/10^6=#

as you can see I split the division into two "easy" bits:

#84/12=7#

#10^2/10^6=10^(2-6)=10^-4=1/10^4#
using the properties of exponents.

Finally, grouping them together:

#8400/(1.2xx10^7)=7*1/10^4=7xx10^-4=0.0007#