How old is Zack now?

That’s a fun brain teaser.

Let’s break it down: Zack got married when he was 25.

Now his kids are 25 years old.

That means 25 years have passed since he got married (because the kids are now 25). So, Zack’s current age = 25 (age at marriage) + 25 (years passed) = 50 years old.

Answer: Zack is 50 now.