4. Which number is NOT a factor of 22 ?

To determine which number is not a factor of 22, it’s important to remember that factors are whole numbers that can divide another number without leaving a remainder. The factors of 22 are 1, 2, 11, and 22. If you're considering numbers like 3, 4, or 5, those definitely do not fit the bill! For example, when you divide 22 by 3, you end up with a messy fraction instead of a nice whole number. If you're ever in doubt, simply test numbers for divisibility. This means taking the number in question (22) and performing division with potential factors. If the result is a whole number, it's a factor; if it's not, it's out of the running!