Question

The Jurassic Period ended about 2.05 × 108 years ago. How many years is this?
A. 20,500,000
B. 2,049,999.9999999998
C. 2,049,999,999.9999998
D. 204,999,999.99999997

Answer 1

\[2.05 * 10^{8}\]

Answer 2

When dealing with powers of 10, move the decimal place over the power of the 10. In this case, you'll more the decimal in 2.05 to right 8 times.

Answer 3

Then, you would have to put commas after every third numbers to separate thousand, millions, billions, etc.