Which expression is equal to 5.1×10^−3

Question

?(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 \(3.9 \times 10^{-3} + 1.2 \times 10^{-3}\).