Civil Service Exam Reviewer · Basic Operations · hard

Multiply: (8 × 104) × (5 × 102). Express in scientific notation.

1. 40 × 108
2. 4 × 105
3. 13 × 106
4. 4 × 107

Answer

D. 4 × 107

Solution

8 × 5 = 40 and 104 × 102 = 106. Normalized: 4 × 107.

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