Math riddles: did you crack them?

In our in our January 2026 newsletter, we challenged readers with a few classic math riddles. Here are the answers—how did you do?

I am a number, but add “G” to me and I go away.
Answer: One (add “G” and it becomes “gone”).

Using only addition, add eight 8s to get 1,000.
Answer: 888 + 88 + 8 + 8 + 8 = 1,000.

What is the smallest number that increases by 12 when flipped upside down?
Answer: 86 (turned upside down, it becomes 98).