Question

Which expression is equal to 5.1×10^−3
?(1 point)
Responses

2.2×10−1+2.9×10−2
2.2 times 10 superscript negative 1 baseline plus 2.9 times 10 negative squared

3.5×103+1.6×10−6
3.5 times 10 cubed plus 1.6 times 10 superscript negative 6 baseline

2.9×10−3+1.2×10−3
2.9 times 10 negative cubed plus 1.2 times 10 negative cubed

3.9×10^−3+1.2×10^−3

Answer 1

To find which expression is equal to \(5.1 \times 10^{-3}\), we can evaluate each of the provided options.

1. **\(2.2 \times 10^{-1} + 2.9 \times 10^{-2}\)**
Convert both terms to have the same exponent:
\[
2.2 \times 10^{-1} = 2.2 \times 10^{-1} = 22 \times 10^{-2}
\]
Then add:
\[
22 \times 10^{-2} + 2.9 \times 10^{-2} = (22 + 2.9) \times 10^{-2} = 24.9 \times 10^{-2} = 2.49 \times 10^{-1}
\]
This is not equal to \(5.1 \times 10^{-3}\).

2. **\(3.5 \times 10^{3} + 1.6 \times 10^{-6}\)**
This cannot equal \(5.1 \times 10^{-3}\) because \(3.5 \times 10^{3}\) is a large number (3500), and adding a small number will not bring it close to \(5.1 \times 10^{-3}\).

3. **\(2.9 \times 10^{-3} + 1.2 \times 10^{-3}\)**
Add both terms:
\[
2.9 \times 10^{-3} + 1.2 \times 10^{-3} = (2.9 + 1.2) \times 10^{-3} = 4.1 \times 10^{-3}
\]
This is not equal to \(5.1 \times 10^{-3}\).

4. **\(3.9 \times 10^{-3} + 1.2 \times 10^{-3}\)**
Add both terms:
\[
3.9 \times 10^{-3} + 1.2 \times 10^{-3} = (3.9 + 1.2) \times 10^{-3} = 5.1 \times 10^{-3}
\]
This is equal to \(5.1 \times 10^{-3}\).

So, the correct expression that is equal to \(5.1 \times 10^{-3}\) is **\(3.9 \times 10^{-3} + 1.2 \times 10^{-3}\)**.