what is the H.C.F of 12,15,21
Answers
Step-by-step explanation:
12=3×2×2
15×3×5
21=3×7
therefore HCF of 12,15,21 is 3
Step-by-step explanation:
If you wanted to take the methodical approach, which you could apply to any combination of numbers, then you would need to first list all of the factors of each number. From there, simply find the common factors, and among those the highest common factors
12: 1, 2, 3, 4, 6, 12
15: 1, 3, 5, 15
21: 1, 3, 7, 21
The only common factors are 1 and 3, and since 3 is greater than 1 then 3 is the highest common factor.
Three other numbers, as another example:
10, 50, 200
10: 1, 2, 5, 10
50: 1, 2, 5, 10, 25, 50
200: 1, 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 200 (pretty sure that’s all of the factors)
The common factors are 1, 2, 5, and 10; the highest common factor, then, is 10.