Question

In February 2010, the population of the world was
approximately 6 800 000 000 people.
Another way of writing this number is
a.6.8 × 10^8
b.6.8 × 10^9
c.68 × 10^9
d. 68 × 10^10

Answer 1

The answer to your question is A.) , because there are 8 zeros which make it to the power of 8, by 10.

Answer 2

The correct choice is 'B'. The correct exponent is +9. In order to change 6.8 into 6,800,000,000 you have to move the decimal point 9 places in the LARGER direction.