Question

14. select the correct answer.what is the sum of $9.72 \times {10}^{8 \: and \: } 1.93 \times {10}^{7}$

Answer 1

In order to sum 9.72 x 10⁸ + 1.93 x 10⁷, consider that it is necessary that both 10 factors have the same exponent.

You can increase the exponent of the second number from 7 to 8, by moving the decimal point one unit to the left, just as follow:

1.93 x 10⁷ = 0.193 x 10⁸

now, you can sum the given numbers:

9.72 x 10⁸ + 0.193 x 10⁸ = 9.913 x 10⁸

where you have added the coefficients of the previous terms.