Back to Perform operations with numbers expressed in scientific notation — Problem 1 · Task Set 18

8.EE.A.4 Tutor Intake -- Operations with Scientific Notation

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every answer helps your tutor plan your first few sessions.

Grade 8·10 problems·~10 min·Common Core Math - Grade 8·container·8-ee-a-4

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Concepts

A student multiplies $(4 \times 10^3)(5 \times 10^6)$ and gets
$20 \times 10^9$ . Is this the final answer in proper scientific
notation, and if not, what is the correct final form?

Not final — 20 is not between 1 and 10, so it must be rewritten as $2.0 \times 10^{10}$ .

This is already the final answer, since $20 \times 10^9$ correctly represents the product.

Not final — the exponent must be reduced to compensate, giving $2.0 \times 10^8$ .

Not final — 20 should be split into two separate powers of 10, giving $2.0 \times 2.0 \times 10^9$ .