Find the LCM Using Prime Factorization
Find the LCM of 6, 18, and 24.To find the least common multiple using prime factorization:Write the prime factorization
for each number.Write each prime factor the
greatest number of times it
appears in any of the numbers.
Then multiply the factors.So the least common multiple of 6, 18, and 24 is 72.6 2 3
18 2 3 324 2 2 2 (^33) appears two times.
Write two 3s.
2 appears three times.
2 2 2 3 3 (^72) Write three 2s.
Find the LCM of each set of numbers. Use prime factorization.
- 3, 7 24.2, 3 25. 7, 21 26.3, 9 27.12, 4 28. 10, 5
- 7, 2 30.11, 5 31. 3, 15 32.16, 32 33.1, 9 34. 12, 1
- 7, 8, 56 36. 8, 10, 40 37.12, 48,72 38. 8, 13, 52
- 5, 9, 27 40. 9, 14, 16 41. 9, 15, 25 42. 4, 14, 49
Tell whether the shortcuts below will help you find the least common
multiple (LCM) of a pair of numbers. Explain using examples.- If both numbers are prime numbers, 46.If one number is a factor of the other,
the LCM is the product of the two. the LCM is the greater of the two.
44. In June, Al has a baseball game every
4th day starting June 4, and a tennis
game every 6th day, beginning June 6.
On which June days will he play both
baseball and tennis? - A grasshopper and a frog start
together and jump along the same
path. The grasshopper always jumps
12 cm and the frog always jumps
15 cm. Will they ever land on the
same spot again? Where?
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