What's the answer of this puzzle?

@Tomorrow Sorry, wrong answer

@ABCDEF7 Ugh. That is tricky and not in a nice way! I didn't notice first time around. I change my answer to...23. If that's not correct - I give up. Lol.

@Tomorrow 23 is right. I have marked best answer who gave it first.

@ABCDEF7 Thanks! I knew my math was right first time around except for....well, you know. 😂

@Tomorrow It happens to most of us 🙂

@ABCDEF7 Lol. I'm sure it does.
I couldn't figure out what I had missed.

@Tomorrow want another math quiz?

@ABCDEF7 Laughs. Should I be aware of trickery afoot this time?

@Tomorrow No, not this sort of

@ABCDEF7 I might not have the skills to answer it. Lol. Sure throw it out there. See what answers you get.

@Tomorrow It's a puzzle you yourself can verify the answer. Can I send you the puzzle in PM?

@ABCDEF7 sure.