Question

(This one is like reading Chinese for me, please help)
The amounts of household waste generated in a region during two years were 23,400,000 tons and 48,100,000 tons. What was the total household waste generated over these two years in the region, expressed in scientific notation?

7.15 ⋅ 107 tons

7.15 ⋅ 1014 tons

71.5 ⋅ 107 tons

71.5 ⋅ 1014 tons

Answer 1

scientific notation takes large numbers and reduces them to something more 'managable' something that is visually less then 10

can we narrow the options knowing this?

Answer 2

the only other thing to consider is the power that is applied to the 10, it counts the number of decimal places that we moved to 'manage' the number with.

since 71,500,000 manages to 7.15 (visually less than 10), we have moved the decimal over 7 places.

7.15 * 10^7 is equal to 71,500,000

7.15 * 10^7 is called scientific notation

Answer 3

So, when you multiply a decimal number with a number that has an exponent it's called scientific notation or?

Answer 4

First, they want you to add the numbers
23,400,000 tons and 48,100,000 tons
I assume you can do that ?

Answer 5

I add those numbers -.-

Answer 6

I can.

Answer 7

once you have the total, rewrite it in scientific notation. Satellite gave the short version

Here is a longer version
http://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-numbers-operations/cc-8th-scientific-notation/v/scientific-notation--old

Answer 8

Thank you :)