Q: How is the number 78,438,142 written in Scientific Notation?
A: 7.8438142 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 78,438,142 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: | 7 | . | 8 | 4 | 3 | 8 | 1 | 4 | 2 |
| 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 = 7.8438142
b = 7
Now the whole thing:
7.8438142 x 107
Check your work:
107 = 10,000,000 x 7.8438142 = 78,438,142
| 78,438,140 | 78,438,141 | 78,438,143 | 78,438,144 |
| 7.843814 x 107 | 7.8438141 x 107 | 7.8438143 x 107 | 7.8438144 x 107 |