What is the greatest common factor of 24 and 42?
2 Answers
Explanation:
Break the numbers down into their prime number factors.
Some prime numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37 ....
Observe that the only prime numbers in both are 2 and 3.
So the product
Since there is no other prime common to both
So, the highest/greatest common factor of
Explanation:
My favourite method for finding the greatest common factor (GCF) of two numbers goes as follows:
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Divide the larger number by the smaller to give a quotient and remainder.
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If the remainder is zero then the smaller number is the GCF.
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Otherwise repeat with the smaller number and the remainder.
In our example we find:
#42/24 = 1# with remainder#18#
#24/18 = 1# with remainder#6#
#18/6 = 3# with remainder#0#
So the GCF is