Here’s another one, from a grade 8 test, same source:

9. What is the decimal notation of 7×10-4? ( they mean 10 to the power 4)

a. 70,000

b. 7,000

c. 0.00007

d. 0.0007

Answer and EXPLANATION!!!!!!!!!!!!!!!!!!!!

9. D: Because the exponent of 10 is -4, the decimal which is located behind the 7 will move 4 spaces to the left, and any of the empty spaces will fill with 0’s. so 7x 10? -4=0.0007

I hope that the computer system used to present these tests can cope better with “strange” symbols. I looked as well behind the 7 and could not see a decimal.

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