Concept 3 of 5
Number Riddles
Today's big idea
Only one number fits every clue
Test the options against all clues.
How it works
👀 What's going on?
'I am a two-digit number. My digits add to five, and I live between twenty and thirty. Who am I?' A number riddle hands you clues, and only one number obeys them all.
💡 Here's the trick
Look at the clues above. Each clue narrows the field. Test the options against every clue and keep only the number that passes all of them.
- 1.Read all the clues before you choose.
- 2.Try each option against the first clue, then the next.
- 3.Keep the one number that fits every clue.
✍️ Try it
I am between 20 and 30, and my two digits add up to 5. Who am I? Between 20 and 30 the tens digit is 2, so the ones digit must be 3 to make 5. The number is 23.
⚠️ Watch out
A number that fits one clue may fail another. 25 is between 20 and 30 but its digits add to 7, so it is out. Check every clue, not just the first.
See it in action
⚡ Time to play!
Test each option against every clue. Only one fits them all.
NUMBER RIDDLE · ROUND 1 OF 3
- • I am between 20 and 30.
- • My two digits add up to 5.
Which number am I?
Quick check
✅ VERIFICATION
I am a 2-digit number. My tens digit is 5 and my ones digit is 2 less than the tens. Who am I?
⚡ Finish the activity above first to answer.
Keep going!
Up next: Balance Puzzles
Apple = 2 bananas × 3 = 6.