The given numbers 240, 321, 418, and 812 can be simplified to 240, 321, 236, and 236. Now, 240 cannot be the smallest, and since we cannot have two correct answers, the answer must be 321.

If there were a need to find the smallest between 236 and 321, we can factorize them to compare, and usually, there is a significant difference so that we don’t have to calculate completely.

For example:
236 = 2 × 2 × 59
321 = 3 × 107

Observing the factors, it’s evident that the second number is smaller.