Answer:
4.2·10⁷
Step-by-step explanation:
Exponents are added when multiplying:
(a^b)(a^c) = a^(b+c)
1.15·10⁵ × 3.65·10² ≈ 4.2·10⁷
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Your calculator is designed to work with scientific notation. Scientific or graphing calculators can also display their output in scientific notation. A spreadsheet can also perform this calculation for you and display the result in the required format.
Calculators and spreadsheets sometimes use "E" in place of "×10^". That is, 4.2E7 means 4.2×10^7.