Question

Select all the expressions that equal 4×10^6

(2×10^8)(2×10^-2)

40×10^5

40^6

400,000

1.2×10^9/3×10^2

Answer 1

• (2×10^8)(2×10^-2)
• 40×10^5
• 1.2×10^9/(3×10^2)

Explanation:

Your calculator or a spreadsheet can help you do this. The rules of exponents apply.

(10^a)(10^b) = 10^(a+b)

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(2×10^8)(2×10^-2) = 4×10^6

40×10^5 = 4×10^6

40^6 = 4.096×10^9

400,000 = 4×10^5

1.2×10^9/3×10^2 = 4×10^10 or 1.2×10^9/(3×10^2) = 4×10^6 (see note)

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Note: A multiplier that is a power of 10 is one factor of a product. A product does not go into the denominator of a fraction unless it has parentheses around it. a/bc = (a/b)c ≠ a/(bc) (This is a consequence of the Order of Operations.)