GCF for 30 and 285

What is the Greatest Common Factor of 30 and 285?

Answer: GCF of 30 and 285 is 15

(Fifteen)

Finding GCF for 30 and 285 using all factors (divisors) listing

The first method to find GCF for numbers 30 and 285 is to list all factors for both numbers and pick the highest common one:

All factors of 30: 1, 2, 3, 5, 6, 10, 15, 30

All factors of 285: 1, 3, 5, 15, 19, 57, 95, 285

So the Greatest Common Factor for 30 and 285 is 15

Finding GCF for 30 and 285 by Prime Factorization

The second method to find GCF for numbers 30 and 285 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 30: 2, 3, 5

All Prime Factors of 285: 3, 5, 19

As we can see there are Prime Factors common to both numbers: 3, 5

Now we need to multiply them to find GCF: 3 × 5 = 15

GCF Table

Number 1Number 2GCF
1528515
162851
172851
182853
1928519
202855
212853
222851
232851
242853
252855
262851
272853
282851
292851
3028515
312851
322851
332853
342851
352855
362853
372851
3828519
392853
402855
412851
422853
432851
442851

About "Greatest Common Factor" Calculator

This calculator will help you find the greatest common factor (GCF) of two numbers. For example, it can help you find out what is the Greatest Common Factor of 30 and 285? (The answer is: 15). Select the first number (e.g. '30') and the second number (e.g. '285'). After that hit the 'Calculate' button.
Greatest Common Factor (GCF) also known as the Greatest Common Divisor (GCD) or Highest Common Factor (HCF) - it is the largest positive integer that divides each of the integers with zero remainder

FAQ

What is the Greatest Common Factor of 30 and 285?

GCF of 30 and 285 is 15