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

May 13, 2016

$1 , 287 , 000 , 000 = 1.287 \setminus \times {10}^{9}$.

#### 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 $a \setminus \times {10}^{n}$ or $a \setminus \times {10}^{- n}$ 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 $1.287 \setminus \times {10}^{9}$.