Q: A number is divisible by 9 if what?

If the sum of its digits is divisible by 9. Example: 729 → 7+2+9=18 → 18 ÷ 9 = 2. This trick helps check divisibility in puzzles quickly.....

Q: Which number fits: 7, 10, 16, 25, ?

Differences: +3, +6, +9 → next difference +12 25 + 12 = 37. Recognizing the pattern in the differences solves the puzzle.....

Q: I think of a number, subtract 7, get 15. What’s the number?

Let x be the number. x − 7 = 15 → x = 22. This is a basic reverse operation, common in number riddles.....

Q: What’s the next square number after 64?

64 is 8², so the next is 9² = 81. Square numbers often appear in puzzle sequences and visual problems. Knowing squares up to 20 is helpful.....

Q: A number is divisible by both 3 and 4. Is it divisible by 12?

Yes, if a number is divisible by both 3 and 4, it's divisible by their LCM: 12. Understanding divisibility and least common multiples is essential in number puzzles.....

Q: What comes next: 1, 1, 2, 3, 5, ?

This is the Fibonacci sequence. Each number is the sum of the two before it. 5 + 3 = 8 → answer is 8. Fibonacci numbers appear....

Q: I am a number. Double me, add 10, you get 30. What am I?

Let the number be x. 2x + 10 = 30 → 2x = 20 → x = 10. Simple algebra helps solve logic puzzles....

Q: Find the odd one: 3, 5, 11, 14, 17.

All numbers are prime except 14. 3, 5, 11, 17 are prime, but 14 = 2 × 7. Spotting prime numbers quickly is useful for solving such puzzles.....

Q: What’s the missing number: 2, 4, 8, 16, ?

The pattern doubles each time: 2 × 2 = 4, then 8, then 16. Next is 16 × 2 = 32. This is a geometric progression. Recognizing multiplication or addition....