Is 21 a multiple of 9?

Understanding Multiples

A multiple of a number is the product of that number and any whole number. In other words, if you can divide 21 evenly by 9 with no remainder, then 21 is a multiple of 9.

For example, multiples of 9 include:

Notice how each number is a product of 9 and a whole number (1, 2, 3, …). This pattern is useful in:

• ✅ Solving math problems like factors and multiples
• ✅ Understanding time intervals (like 15, 30, 45, 60 minutes)
• ✅ Money calculations (coins, bills, and budgets)
• ✅ Everyday patterns, construction measurements, or repeating sequences

So, knowing whether a number is a multiple of another helps in quick calculations, spotting patterns, and making problem-solving easier.

Quick Tips

• If 21 < 9, then 21 cannot be a multiple of 9.
• If 21 is divisible by 9 with remainder 0, it is a multiple.
• Using multiples is a key concept in fractions, ratios, and modular arithmetic.