How do you write the answer in scientific notation given #(2.1times10^-4)/(8.4times10^-6)#?

2 Answers

#2.5xx10^1#

Explanation:

#(2.1xx10^(-4))/(8.4xx10^(-6))#

#=0.00021/ 0.0000084#

#=2100/ 84#

# =25#

#=2.5 xx10^1#

Apr 16, 2017

#2.5 xx 10^1#

Explanation:

Use the exponent rule #x^m/x^n = x^(m-n)#

#(2.1 xx 10^-4)/(8.4 xx 10^-6) = 2.1/8.4 xx 10^(-4- -6) = 0.25 xx 10^2#

Scientific notation requires a non-zero number to be to the left of the decimal point. This means you need to move the decimal to the right one place which decreases the exponent by 1:

#0.25 xx 10^2 = 2.5 xx 10^1#