Common factor of 60 and 45?

Answer 1

Common factors: 3, 5, 15.

HCF: 15.

To work out:

Make a factor tree or ladder. (Ignore the dashes)

----45

---/---\

--3----15

-------/---\

------3----5

We cannot go any further as 3 & 5 are prime.

Therefore 45 = 3 x 3 x 5.

(same with 60) 60 = 2 x 2 x 3 x 5.

The easiest way is to now make a venn diagram. Put the numbers that appear in both lists in the intersection. (3 and 5 but do not put both threes in)

my venn diagram--->(3)(3, 5) (1, 2)

Then, times the numbers in the intersection together... and voila! You get 15 which is the HCF!

--To find the LCM, multiply all the numbers in the VENN DIAGRAM together. =] \AT

Answer 2

The common factors of 60 and 45 are 1, 3,5, and 15.

Answer 3

1, 3, 5 and 15

Answer 4

4 and 3