New York County had a population of about #1.54 \times 10^6# people in 2000. Erie had a population of about #9.5 \times 10^5# people. What was the combined population of the two counties?

1 Answer
Sep 29, 2017

See a solution process below:

Explanation:

The combined population is:

#(1.54 xx 10^6) + (9.5 xx 10^5)#

There are a couple of ways we can simplify this expression. First, we can convert to standard terms, add the numbers and the convert back to scientific notation:

#1,540,000 + 950,000 = 2,490,000 = 2.49 xx 10^6#

Another way is to rewrite one of the terms in the original expression so there are common denominators with the 10s terms:

#1.54 xx 10^6 = 15.4 xx 10^5#

We can rewrite the original expression as:

#(15.4 xx 10^5) + (9.5 xx 10^5) =#

#(15.4 + 9.5)10^5 =#

#24.9 xx 10^5 =#

#2.49 xx 10^6#