You know the following information:
1. The amount of money (in dollars) earned last year was:
2. The amount of money (in dollars) earned this year, is:
Then, to estimate the sum (the total amount of money the Software Company earned in those two years, you can round the numbers to the nearest billion.
Having:
You need to look at the digit located in the Hundred millions place. Notice that this is:
Then, since:
You need can't round up. Then:
Now, having:
You can identify that the digit in the Hundred millions place is
Therefore:
Now you can add the numbers rounded:
Hence, the answer is: Option B.