What is the HCF of 180 and 210?

Answer 1

The GCF is 30.

Answer 2

Hi!

Here is an easy method to find the HCF of absolutely any pair of numbers.

Step 1

Find the difference between the numbers.

x - y = z

Step 2

Ask this question, 'Is z a factor of x and y?'

Another way to ask this question is, 'Are x and y in z's timetable?'

If the answer is 'YES', then z is the HCF/ GCF.

It's as simple as that.

All you have to do is substitute the letters with the numbers that you were given in the question.

Let's take 9 & 12 as examples.

12 - 9 = 3

Is 3 a factor of 12 and 9? Yes

Are 12 and 9 in 3's timetable? Yes (3 x 3 = 9, 3 x 4 = 12)

HCF/ GCF = 3

According to your question, the numbers are 180 and 210.

210 - 180 = 30

Is 30 a factor of 210 and 180? Yes

Are 210 and 180 in 30's timetable? Yes (30 x 60 = 180, 30 x 70 = 210)

HCF/GCF = 30

DISCLAIMER: This only works on two numbers.

You can ask one question. It isn't necessary to ask both questions.

Answer 3

The HCF of 180 and 210 is 30.

Answer 4

30

Answer 5

2