What is the Least Common Multiple of 9 and 21?

The least common multiple (LCM) of 9 and 21 is 63. To find the LCM, you can use the prime factorization method. To do this, you will first find the prime factorization of 9 and 21. 9 = 3 x 3 and 21 = 3 x 7. Then, multiply each factor the maximum number of times it occurs in either number. The LCM of 9 and 21 is 3 x 3 x 7 = 63.

The least common multiple of 9 and 21 is 63. It is the smallest number that is divisible by both 9 and 21. To find the LCM of 9 and 21, you can use either the LCM Formula Calculation of Greatest Common Factor (GCF) or the Prime Factorization Method. Using the LCM Formula Calculation of GCF, the LCM of 9 and 21 is (9 x 21) / 9 = 189 / 9 = 21. Using the Prime Factorization Method, the LCM of 9 and 21 is 3 x 3 x 7 = 63. The prime factorization of 9 is 3 x 3 and the prime factorization of 21 is 3 x 7. To find the LCM with this method, you need to multiply each factor the greater number of times it occurs in the prime factorization. In this case, 3 occurs twice in the prime factorization of 9 and once in the prime factorization of 21, so the LCM is 3 x 3 x 7 = 63.