Question

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

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

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

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

3.9×10−3+1.2×10−3
3.9 times 10 negative cubed plus 1.2 times 10 negative cubed

Answer 1

To find which expression is equal to \(5.1 \times 10^{-3}\), we will evaluate each response.

1. **\(2.9 \times 10^{-3} + 1.2 \times 10^{-3}\)**:
\[
2.9 \times 10^{-3} + 1.2 \times 10^{-3} = (2.9 + 1.2) \times 10^{-3} = 4.1 \times 10^{-3}
\]
This is **not equal** to \(5.1 \times 10^{-3}\).

2. **\(3.5 \times 10^{3} + 1.6 \times 10^{-6}\)**:
This equals a very large number plus a very small number, and clearly is **not equal** to \(5.1 \times 10^{-3}\).

3. **\(2.2 \times 10^{-1} + 2.9 \times 10^{-2}\)**:
Convert \(2.2 \times 10^{-1}\) to \(10^{-3}\):
\[
2.2 \times 10^{-1} = 22 \times 10^{-3}
\]
Now \(2.9 \times 10^{-2}\) converted to \(10^{-3}\) is:
\[
2.9 \times 10^{-2} = 29 \times 10^{-3}
\]
Adding these together:
\[
22 \times 10^{-3} + 2.9 \times 10^{-2} = 22 \times 10^{-3} + 29 \times 10^{-3} = 51 \times 10^{-3} = 5.1 \times 10^{-2}
\]
As seen, this is also **not equal** to \(5.1 \times 10^{-3}\).

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

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