Q: How is the number 138,720,474 written in Scientific Notation?
A: 1.38720474 x 108
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 138,720,474 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: | 1 | . | 3 | 8 | 7 | 2 | 0 | 4 | 7 | 4 |
| Decimal Count: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
There are 8 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 = 1.38720474
b = 8
Now the whole thing:
1.38720474 x 108
Check your work:
108 = 100,000,000 x 1.38720474 = 138,720,474
| 138,720,472 | 138,720,473 | 138,720,475 | 138,720,476 |
| 1.38720472 x 108 | 1.38720473 x 108 | 1.38720475 x 108 | 1.38720476 x 108 |