Question

a researcher measured approximately 0.005123 grams of bacteria in a sample. what is the value of the exponent when this number is written in scientific notation?

Explanation:

Step1: Recall scientific - notation form

Scientific notation is $a\times10^{n}$, where $1\leqslant|a|\lt10$ and $n$ is an integer.

Step2: Rewrite the number

For the number $0.005123$, we move the decimal point 3 places to the right to get a number $a = 5.123$ which satisfies $1\leqslant|a|\lt10$. So, $0.005123=5.123\times10^{- 3}$.

Answer:

$-3$