Read this if you're new to the topic—it will help you know what to do in each problem.

A number is divisible by another if it divides evenly (no remainder). We often check divisibility by 2, 3, 5, or 10.

Rules: divisible by 2 if the last digit is even; by 5 if it ends in 0 or 5; by 10 if it ends in 0. For 3, add the digits—if that sum is divisible by 3, the number is too.