Question

1. According to the U.S. Energy Information Administration (www.eia.gov) the United States consumed 4.151 trillion kWh (kilowatt-hours) of electric energy in 2010. Write this number in correct scientific notation in terms of kWh. 4.151 X 10^12

2. Of this electric energy, 260.2 billion kWh were produced by hydroelectric sources (think water over dams – like Snoqualmie Falls) in 2010.

1. a) Write this number in correct scientific notation in terms of kWh. 2.602 x 10^11

2. b) What percent of the total US electric energy did hydroelectric sources

   account for in 2010? (Round to the nearest 10th of a percent.) 6.27%

3. Additionally, 94.7 billion kWh were produced by wind power sources.

1. a) Write this number in correct scientific notation in terms of kWh. 9.47 X 10^10

2. b) What percent of the total US electric energy did wind power sources

   account for in 2010? (Round to the nearest 10th of a percent.) 2.29%

3. c) What percent of the total US electric energy did hydro and wind power

   sources account for in 2010 combined? 8.55%

5. On average, an American household used 11,698 kWh in 2010.
a) How many American households could have been powered completely on hydro and wind power in

2010? Write your answer in correct scientific notation rounding to 3 decimal places.

2. b) If there were 116.7 million households in 2010, your answer to part a) is what percentage of all American households? (Round to the nearest 10th of a percent.)

3. c) If done correctly, your answer to 5b) doesn’t match your answer to 3c), though it seems it should. Why is this?

This is for question 5. The rest above are answered and might go with question 5.

Answer 1