Greatest Common Factor of 18/28, 78/70, 20/90, 45/154

Created By : Jatin Gogia

Reviewed By : Rajasekhar Valipishetty

Last Updated : Apr 06, 2023


GCF of 18/28, 78/70, 20/90, 45/154

Enter two or more fractions separated by "commas"

Ex: 2/3, 5/7 or 3/5, 5/9, 7/3

GCF of:

Greatest Common Factor of 18/28,78/70,20/90,45/154

Given fractions are 18/28,78/70,20/90,45/154

Formula to find GCF of Fractions is

GCF = GCF of Numerators/LCM of Denominators

As per the formula GCF of Fractions let’s split into two parts and find the GCF of Numerators and LCM of Denominators

In the given fractions GCF of Numerators means GCF of 18,78,20,45

Greatest Common Factor of Numerators i.e. GCF of 18,78,20,45 is 1 .

LCM of Denominators means LCM of 28,70,90,154 as per the given fractions.

LCM of 28,70,90,154 is 13860 as it is the smallest common factor for both these numbers.

Lets's calculate GCF of 18,78,20,45

GCF of Fractions 18/28,78/70,20/90,45/154 is 1/13860

∴ So GCF of numbers is 1 because of no common factors present between them.

Greatest Common Factor of 18,78,20,45 By Matching Biggest Common Factor Method

Greatest Common Factor of 18,78,20,45 By Matching Biggest Common Factor Method

Factors of 18

List of positive integer factors of 18 that divides 18 without a remainder.

1,2,3,6,9,18

Factors of 78

List of positive integer factors of 78 that divides 78 without a remainder.

1,2,3,6,13,26,39,78

Factors of 20

List of positive integer factors of 20 that divides 20 without a remainder.

1,2,4,5,10,20

Factors of 45

List of positive integer factors of 45 that divides 45 without a remainder.

1,3,5,9,15,45

Greatest Common Factor

We found the factors 18,78,20,45 . The biggest common factor number is the GCF number.
So the greatest common factor 18,78,20,45 is 1.


Lets's calculate LCM of 28,70,90,154

2 28, 70, 90, 154
5 14, 35, 45, 77
7 14, 7, 9, 77
2, 1, 9, 11

∴ So the LCM of the given numbers is 2 x 5 x 7 x 2 x 1 x 9 x 11 = 13860

Thus GCF of Fractions = GCF of Numerators/LCM of Denominators = 1/13860

Therefore, the GCF of Fractions 18/28,78/70,20/90,45/154 is 1/13860

Least Common Multiple of 28,70,90,154 with GCF Formula

Least Common Multiple of 28,70,90,154 with GCF Formula

The formula of LCM is LCM(a1,a2,a3....,an) = ( a1 × a2 × a3 × .... × an) / GCF(a1,a2,a3....,an) x common factors(if more than 2 numbers have common factors).

We need to calculate greatest common factor of 28,70,90,154 and common factors if more than two numbers have common factor, than apply into the LCM equation.

GCF(28,70,90,154) = 2

common factors(in case of two or more numbers have common factors) = 980

GCF(28,70,90,154) x common factors =2 x 980 = 1960

LCM(28,70,90,154) = ( 28 × 70 × 90 × 154 ) / 1960

LCM(28,70,90,154) = 27165600 / 1960

LCM(28,70,90,154) = 13860


GCF of Fractions Calculation Examples

Here are some samples of GCF of Fractions calculations.

GCF of Fractions Calculation Examples

Frequently Asked Questions on Fractional GCF of 18/28, 78/70, 20/90, 45/154

1. How to find GCF in Fractions?

Answer: GCF of fractions can be found using the simple formula GCF of Fractions = GCF of Numerators/LCM of Denominators.

2. What is the GCF of Fractions for 18/28, 78/70, 20/90, 45/154?

Answer: GCF of Numerators as per given numbers 18/28, 78/70, 20/90, 45/154 is

GCF of Numerators i.e. for 18,78,20,45 is 1

LCM of denominators i.e. for 28,70,90,154 is 13860.

Thus, GCF of Fractions is 1/13860.Finally, GCF of Fractions for 18/28, 78/70, 20/90, 45/154 is 1/13860.