I am a number less than 100. When divided by 5, my remainder is 4. When divided by 7, my remainder is 3. What is the lowest positive number I could be?
39
Multiples of 7 plus 3: 3, 10, 17, 24, 31, 38, 45... Testing for remainder 4 when divided by 5: 39 divided by 5 leaves 4, and 39 divided by 7 leaves 4? Wait. 39 / 7 = 5 with a remainder of 4. Let's check: 39 / 7 = 5 R 4. Not 3. Let's use 52: 52 / 7 = 7 R 3. 52 / 5 = 10 R 2. Let's find correct number: 24. 24 / 5 = 4 R 4. 24 / 7 = 3 R 3. Both conditions met! 24.
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.
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