Evaluate Using Scientific Notation (4.010^-1)(2.5*10^-4)

$(4 \cdot 10^{- 1}) \cdot (2.5 \cdot 10^{- 4})$

Group coefficients together and exponents together to multiply numbers in scientific notation.

$(4 \cdot 2.5) (10^{- 1} \cdot 10^{- 4})$

Multiply $4$ by $2.5$ .

$10 (10^{- 1} \cdot 10^{- 4})$

Multiply $10^{- 1}$ by $10^{- 4}$ by adding the exponents.

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$10 \cdot 10^{- 1 - 4}$

Subtract $4$ from $- 1$ .

$10 \cdot 10^{- 5}$

Write $10 \cdot 10^{- 5}$ in proper scientific notation.

$1 \cdot 10^{- 4}$

Multiply $10^{- 4}$ by $1$ .

$10^{- 4}$

Rewrite the expression using the negative exponent rule $b^{- n} = \frac{1}{b^{n}}$ .

$\frac{1}{10^{4}}$

Raise $10$ to the power of $4$ .

$\frac{1}{10000}$

Evaluate Using Scientific Notation (4.0*10^-1)*(2.5*10^-4)