I am a two-digit number. My tens digit is 3 greater than my units digit. If you swap my digits to form a new number and subtract that new number from me, what result do you get?
27
Let tens digit be u+3 and units digit be u. Original number is 10(u+3) + u = 11u + 30. Reversed is 10u + (u+3) = 11u + 3. The difference is (11u + 30) - (11u + 3) = 27.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
More math riddles
Eli makes 5 rows of 2 turkeys and adds 1 more at the end. How many turkeys are there in all?
I am a two-digit prime number. Reverse my digits, and I am still prime. My tens digit is greater than my units digit, and the sum of my digits is 10. What number am I?
A book has 300 pages. How many individual pages have a page number containing the digit 3 at least once?
I am the only number whose English name has the exact same number of letters as its numerical value. What am I?
Rotate me on my side, and I represent boundless infinity. Slice me horizontally across my waist, and two identical round circles emerge. Which single digit am I?
Sam has 19 flowers and Max has 3. How many more flowers does Sam have?