Learn Before
Example

Multiplying (4×105)(2×107)(4 \times 10^5)(2 \times 10^{-7}) and Converting to Decimal Form

Multiply (4×105)(2×107)(4 \times 10^5)(2 \times 10^{-7}) and express the result in standard decimal form by applying Properties of Exponents and the Commutative Property.

Step 1 — Rearrange the factors. Use the Commutative Property of Multiplication to group the numerical coefficients together and the powers of 1010 together:

421051074 \cdot 2 \cdot 10^5 \cdot 10^{-7}

Step 2 — Multiply the coefficients and apply the Product Property. Multiply the numerical parts: 42=84 \cdot 2 = 8. For the powers of 1010, both factors share the base 1010, so add the exponents using the Product Property for Exponents: 105107=105+(7)=10210^5 \cdot 10^{-7} = 10^{5 + (-7)} = 10^{-2}. The result in scientific notation is:

8×1028 \times 10^{-2}

Step 3 — Convert to decimal form. The exponent is 2-2, so move the decimal point 22 places to the left: 80.088 \rightarrow 0.08.

Therefore, (4×105)(2×107)=0.08(4 \times 10^5)(2 \times 10^{-7}) = 0.08.

This example illustrates the general strategy for multiplying numbers in scientific notation: rearrange factors so that the coefficients and powers of 1010 are grouped separately, multiply the coefficients, add the exponents on the base 1010, and then convert the result to the desired form.

0

1

Updated 2026-04-21

Contributors are:

Who are from:

Tags

OpenStax

Elementary Algebra @ OpenStax

Ch.6 Polynomials - Elementary Algebra @ OpenStax

Algebra

Math

Prealgebra

Related
Learn After