Question

What is 5.5 x 10^4 multiplied by 2.2 x 10^-8? Write the answer in scientific notation.

12.1 x 10^-4
1.21 x 10^-4
1.21 x 10^-3
1.21 x 10^-5

Answer 1

To multiply the two numbers in scientific notation \(5.5 \times 10^4\) and \(2.2 \times 10^{-8}\), you can follow these steps:

1. **Multiply the coefficients**:
\[
5.5 \times 2.2 = 12.1
\]

2. **Add the exponents**:
\[
10^4 \times 10^{-8} = 10^{4 + (-8)} = 10^{-4}
\]

3. **Combine the results**:
\[
12.1 \times 10^{-4}
\]

4. **Convert to proper scientific notation**: In scientific notation, the coefficient should be between 1 and 10. To convert \(12.1\) to proper scientific notation, you move the decimal point one place to the left, which increases the exponent by 1:

\[
12.1 \times 10^{-4} = 1.21 \times 10^{-3}
\]

So the answer in scientific notation is:

\[
\boxed{1.21 \times 10^{-3}}
\]