How to simplify #(6.3 times 10^5) ÷ (9 times 10^3)# in scientific notation?

1 Answer
Mar 18, 2018

Answer:

#7.0xx10#

Explanation:

#6.3xx10^5# is the same value as #63xx10^4#

So we have:

#(63xx10^4)/(9xx10^3) color(white)("ddd") -> color(white)("ddd") 63/9xx10^4/10^3#

# color(white)("ddddddddd.d")->color(white)("ddd")63/9xx10#

If the sum of the digits is exactly divisible by 3 then the actual number is also exactly divisible by 3 #->6+3=9# so we will divide both top and bottom by 3 to simplify the fraction.

# color(white)("ddddddddd.d")->color(white)("ddd")(63-:3)/(9-:3)xx10#

Note that:

#(63-:3)/(9-:3)=(21-:3)/(3-:3)=7/1=7# so we have:

#(6.3xx10^5)-:(9xx10^3) =7.0xx10#