Question

Susan was given the following number to convert to scientific notation: 12,050,000 Her answer was 1.25 x 10^7 , but it was marked wrong on her paper. Why?

( LOOK AT THE PICTURE TO SEE THE ANSWER CHOICES )

PLEASE HELP

Answer 1

C. She left out a zero between the two and the five

Explanation:

Given that Susan is expected to convert 12,050,000 to scientific notation, what Susan should have done is shown below:

Count the number of decimal places from your right up to before the first digit, and place the decimal point after the first digit. The number of decimal places counted would determine the exponent we are to use.

Here, we have 7 decimal places, counting from the right to the left, therefore, the exponent would be a positive 7.

What Susan should have is:

1.205 × 10⁷ NOT 1.25 × 10⁷.

1.25 × 10⁷ = 12,500,000, which is different from 12,050,000.

Her paper was marked wrong because: "she left out a zero between the two and the five"