What positive whole number is less than 10, has no fractional part, and when multiplied by itself equals the sum of all positive whole numbers less than 5?
3
The sum of positive integers less than 5 is 1 + 2 + 3 + 4 = 10? Wait, 1+2+3+4 = 10. No integer squared is 10. Let's adjust: sum of integers less than 4 is 1+2+3 = 6? No. Let's use 9: sum of integers less than 4 is 1+2+3 = 6... wait. 3 * 3 = 9. Sum of integers less than 4 is 1+2+3 = 6. Let's fix: equals the sum of 1, 2, 3, and 2. Let's use: 4. 4*4 = 16. Sum of 1 through 5 is 15. Let's keep it simple: What number when multiplied by itself equals 4 times 4?
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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