A number leaves a remainder of 23 when divided by 36. What remainder will it leave when divided by 4?

💡 Solution & Explanation

The number can be written as 36n + 23 for some whole number n. Since 36 = 4 × 9, the part 36n divides exactly by 4. So only 23 matters: 23 ÷ 4 leaves a remainder of 3. This works only because 4 is a factor of 36.