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

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 $2.0 \times 2.0 \times 10^9$.

Rewrite $4 \times 10^3$ as $0.04 \times 10^5$ so both terms share the same power of 10, then add the coefficients.

Add the exponents directly, giving a result with $10^{5+3} = 10^8$.

Add the coefficients directly (3 + 4 = 7) without changing either exponent.

Multiply the two numbers together instead, since both involve powers of 10.

$3.5 \times 10^8 = 350{,}000{,}000$

$3.5^8$, which is approximately 22,519

$3.5 \times 8 = 28$

$3.5 \times 10^{-8}$, a very small number