Q: How is the number 66,990,405 written in Scientific Notation?
A: 6.6990405 x 107
The purpose of scientific notation is for scientists to write very large, or very small, numbers with ease.
Calculating scientific notation for a positive integer is simple, as it always follows this notation:
a x 10b
Follow the steps below to see how 66,990,405 is written in scientific notation.
To find a, take the number and move a decimal place to the right one position.
Now, to find b, count how many places to the right of the decimal.
| New Number: | 6 | . | 6 | 9 | 9 | 0 | 4 | 0 | 5 |
| Decimal Count: | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
There are 7 places to the right of the decimal place.
Building upon what we know above, we can now reconstruct the number into scientific notation.
Remember, the notation is: a x 10b
a = 6.6990405
b = 7
Now the whole thing:
6.6990405 x 107
Check your work:
107 = 10,000,000 x 6.6990405 = 66,990,405
| 66,990,403 | 66,990,404 | 66,990,406 | 66,990,407 |
| 6.6990403 x 107 | 6.6990404 x 107 | 6.6990406 x 107 | 6.6990407 x 107 |