What’s the last digit of the following?
171999 + 111999 – 71999
Enter your answer in the comments section below.
Update and Solution
Mike saw through this one early, only his comment was so cryptic I missed it. See below. I didn’t see it until I started working through it, then I thought, “too easy.” Here is how it works.
A is the last digit of 171999. B is the last digit of 111999. C is the last digit of 71999.
It is obvious A = C, so the answer is B. And B is 1.