# Gcf of 9 18 and 24 relationship

### calculate the GCF (greatest common factor) of (9,18,24) gcf(9,18,24) Tiger Algebra Solver How to find the greatest common factor. The greatest common factor of two or more whole numbers is the 1, 2, 3, 4, 6, 9, 12, 18, and The greatest common factor of two or more whole numbers is the largest whole number that divides evenly into The common factors of 18 and 27 are 1, 3 and 9. The factors of are 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, The Greatest Common Factor is the largest whole number that divides Similarly ,. F54 = {1,2,3,6,9,18,27,54}. Thus, 42 = 24 · 1 + 18 GCF(42,24) = GCF(24,18).

## GCF & LCM word problems

Hence write down the LCM of 12, 16 and 24? Solution a The multiples of 12 are 12, 24, 36, 48, 60, 72, 84, 96,,… The multiples of 16 are 16, 32, 48, 64, 80, 96,,… Hence the common multiples of 12 and 16 are 48, 96, ,… and their LCM is Two or more nonzero numbers always have a common multiple — just multiply the numbers together.

But the product of the numbers is not necessarily their lowest common multiple. What is the general situation illustrated here? Solution The LCM of 9 and 10 is their product The common multiples are the multiples of the LCM You will have noticed that the list of common multiples of 4 and 6 is actually a list of multiples of their LCM Similarly, the list of common multiples of 12 and 16 is a list of the multiples of their LCM This is a general result, which in Year 7 is best demonstrated by examples.

In an exercise at the end of the module, Primes and Prime Factorisationhowever, we have indicated how to prove the result using prime factorisation. The whole number factors are numbers that divide evenly into the number with zero remainder.

• Greatest Common Factor GCF Calculator
• Relationship between H.C.F. and L.C.M.
• The Greatest Common Factor

Given the list of common factors for each number, the GCF is the largest number common to each list. Find the GCF of 18 and 27 The factors of 18 are 1, 2, 3, 6, 9, The factors of 27 are 1, 3, 9, The common factors of 18 and 27 are 1, 3 and 9. The greatest common factor of 18 and 27 is 9. Find the GCF of 20, 50 and The factors of 20 are 1, 2, 4, 5, 10, The factors of 50 are 1, 2, 5, 10, 25, The factors of are 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, The common factors of 20, 50 and are 1, 2, 5 and Include only the factors common to all three numbers.

And then after the fifth test, they're going to get to And if there's a sixth test, then they would get to And we could keep going on and on in there. But let's see what they're asking us. What is the minimum number of exam questions William's or Luis's class can expect to get in a year? Well the minimum number is the point at which they've gotten the same number of exam questions, despite the fact that the tests had a different number of items.

And you see the point at which they have the same number is at This happens at They both could have exactly questions even though Luis's teacher is giving 30 at a time and even though William's teacher is giving 24 at a time. And so the answer is And notice, they had a different number of exams. Luis had one, two, three, four exams while William would have to have one, two, three, four, five exams. But that gets them both to total questions.

Now thinking of it in terms of some of the math notation or the least common multiple notation we've seen before, this is really asking us what is the least common multiple of 30 and And that least common multiple is equal to Now there's other ways that you can find the least common multiple other than just looking at the multiples like this.

You could look at it through prime factorization. So we could say that 30 is equal to 2 times 3 times 5.

### GCF & LCM word problems (video) | Khan Academy

And that's a different color than that blue-- 24 is equal to 2 times So 24 is equal to 2 times 2 times 2 times 3. So another way to come up with the least common multiple, if we didn't even do this exercise up here, says, look, the number has to be divisible by both 30 and If it's going to be divisible by 30, it's going to have to have 2 times 3 times 5 in its prime factorization.

That is essentially So this makes it divisible by And say, well in order to be divisible by 24, its prime factorization is going to need 3 twos and a 3. Well we already have 1 three. And we already have 1 two, so we just need 2 more twos.

### Relationship between H.C.F. and L.C.M. | Highest common Factor | Solved Examples

So 2 times 2. So this makes it-- let me scroll up a little bit-- this right over here makes it divisible by And so this is essentially the prime factorization of the least common multiple of 30 and You take any one of these numbers away, you are no longer going to be divisible by one of these two numbers.

If you take a two away, you're not going to be divisible by 24 anymore. If you take a two or a three away. If you take a three or a five away, you're not going to be divisible by 30 anymore.