How do you calculate #8 times10^6 ÷ 4 times 10^2#?

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Answer 1 · 2016-05-08T19:45:17

#20,000 = 2 xx 10^4#

First you put the numbers out of standard form:

#10^6=1,000,000#

#8xx1,000,000=8,000,000#

#4xx10^2=400#

Now the problem is like this:

#8,000,000÷400#

Cancel out some of the zeros so that the division is easier:

#80,000÷4= 20,000#

#= 2 xx 10^4#

(Answers are generally given in the same form in which they are asked.)

Answer 2 · 2016-05-08T20:05:23

#2xx10^4#
(see below for possible alternative answer)

Assuming everything should be left in scientific notation
and that the expression was intended to be (not PEDMAS form)

#color(white)("XXX")(8xx10^6)div(4xx10^2)#

#color(white)("XXX")=8/4xx (10^6)/(10^2)#

#color(white)("XXX")=2xx10^4#

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Technically applying PEDMAS multiplication and division should be done in order from left to right.
So
#color(white)("XXX")8xx10^6div4xx10^2#

#color(white)("XXX")=8,000,000div4xx10^2#

#color(white)("XXX")=2,000,000xx10^2#

#color(white)("XXX")=200,000,000#

#color(white)("XXX")=2xx10^8#

...however, I suspect the parenthesized version is what was intended.