Final answer:
In scientific notation, the coefficient is a number from 1 to 10 multiplied by a power of 10, which represents the number of decimal places moved to convert a number to this format.
Step-by-step explanation:
The first factor in an expression in scientific notation is the coefficient, which must be a number equal to or greater than 1 and less than 10. The coefficient is then multiplied by a power of 10 to represent the original number accurately.
For example, to write the number 79,345 in scientific notation, one would express it as 7.9345 × 104, because we have moved the decimal place to make 79,345 into 7.9345 while recording that we have moved the decimal place four positions to the right, hence the power of 10 being 4.