The multiples of 18 include 36, 54, 72 and 90. An infinite number of multiples of 18 can be achieved by adding 18 to each subsequent multiple. For example, when 18 is added to 90, the sum is 108, which is also a multiple of 18 because 18 times 6 equals 108.
A multiple is a number that is the result of multiplying a number by any integer. A number is identified as a multiple of another number if the first is divisible by the second without any remainder. For example, 90 is a multiple of 18. When 90 is divided by 18, the answer is 5. When 92 is divided by 18, the answer is 5 with a remainder of 2. That means 92 is not a multiple of 18.
The concept of multiples is generally taught in elementary math during and following lessons about multiplication. Understanding multiples becomes important in later elementary math lessons, and multiples are used in algebra and higher-level math as well. A basic function in many math problems involves locating the least-common multiple. Least-common multiples let individuals convert fractions and solve various types of math problems. Basic multiples are also at work when individuals count money, tell time or perform other common tasks.