Question

How do you write `1,287,000,000` in scientific notation?

Answer 1

`1,287,000,000=1.287\times10^9`.

Explanation:

To put a number into scientific notation:

1. Move the decimal point right or left until one nonzero digit is to the left of the moved decimal point. Call the number with the moved decimal point `a`.

2. Count the number of places you moved the decimal point, call it `n`. If you moved the decimal point to the left, that is a factor of `10^n` versus the original number. If you moved the decimal point to the right, that is a factor of `10^{-n}`.

3. The original number in scientific notation is `a\times10^n` or `a\times10^{-n}` depending on which way you used the decimal point.

This for `1,287,000,000` we get

`a=1.287`

by moving the decimal point nine places (`n=9`)

to the left (`n` has the positive sign).

Thus `1.287\times10^9`.