Question

HELP PLEASE!

Express your answer in scientific notation.

9.3 X 107 - 3.14 X 106

Question 2 options:

8.1 X 107


8.1 X 106


8.98 X 107


8.98 X 106

Answer 1

on this question it would be 8 . 98

Answer 2

`8.986* 10^(7) = 8.98 * 10^(7)`

Explanation:

The given expression is

`9.3* 10^(7)-3.14 * 10^(6)`

To solve this, we first need to have the like powers, that is, they must have the same exponent. To obtain such equivalence, we move the decimal point one spot to the right on the first term, that will decrease its exponent by one

`93* 10^(6)-3.14 * 10^(6)`

Now, we extract common factors and subtract

`(93-3.14) * 10^(6)=89.86* 10^(6)`

However, the whole part of the decimal number of the scientific notation can only be between 0 and 10, and we have 89, to solve this problem, we move the decimal point one spot to the left

`8.986* 10^(7) = 8.98 * 10^(7)`

Therefore, the right answer is the third choice.