Question

Which number is greatest?

2.89x10^-8
1.997x10^2
8.9x10^-6
5x10^-6

Answer 1

The second one, because 10^2 (Positive).

Answer 2

B.
`1.997* 10^(2)`

Explanation:

We have been given numbers in scientific notation. We are asked to choose the greatest number from our given choices.

We can see that three of our given numbers has negative exponents and we can represent a negative exponent using property
`a^-b=(1)/(a^b)` as:

A.
`2.89* 10^(-8)=2.89* (1)/(10^8)=0.0000000289`

B.
`1.997* 10^(2)=199.7`

C.
`8.9* 10^(-6)=8.9* (1)/(10^6)=0.0000089`

D.
`5* 10^(-6)=5* (1)/(10^6)=0.000005`

We can see that the number with larger negative power has smallest value.

Therefore,
`1.997* 10^(2)` is the greatest.