Question

The average human body cell is about 5.1 \cdot 10^{-4} \text{ cm}5.1⋅10 −4 cm5, point, 1, dot, 10, start superscript, minus, 4, end superscript, start text, space, c, m, end text in diameter. The diameter of a plant cell is 8 \cdot 10^{-3} \text { cm}8⋅10 −3 cm8, dot, 10, start superscript, minus, 3, end superscript, start text, space, c, m, end text. What is the combined diameter of the body cell and plant cell? Express your answer in scientific notation.

Answer 1

8.51 x 10^-3

Explanation:

khan

Answer 2

`8.51 * 10^(-3) \ cm`

Explanation:

According to the proble, a human body cell is
`5.1 * 10^(-4) \ cm`, and a plant cell is
`8 * 10^(-3) \ cm`.

So, the combined diameter of these cells refers to the sum of these scientific notation numbers. To be able to sum these number, we need them to have the same power with the same exponent, that's why we'll move the decimal point in one number in order to achieve that.

`0.51 * 10^(-3) \ cm`

Now, we sum them

`0.51 * 10^(-3) + 8 * 10^(-3) =(0.51 + 8) * 10^(-3)=8.51 * 10^(-3)`

Notice that we extracted the common power, that's why we needed to have them equal.

Therefore, the combined diameter is
`8.51 * 10^(-3) \ cm`