How do you multiply #(6.4*10^4)(8.6*10^8)#?

2 Answers
Apr 2, 2015

Multiply the numbers and add the #10#powers:

#(6.4*10^4)(8.6*10^8)=(6.4*8.6)*10^(4+8)#

#=55*10^12=5.5*10^13#

(decimal point one to the left = power up by one)

Apr 2, 2015

The answer is #5.5xx10^13#.

First, multiply the coefficients and add the exponents.

#(6.4xx10^4)(8.6xx10^8)=(6.4)(8.6)xx10^((4+8))=55xx10^12#

Second, move the decimal to the left one place and increase the exponent by one so that the answer is in the correct scientific notation format.

#55xx10^12=5.5xx10^13#