How to calculate HCF and LCM of Fractions

Let’s take two fractions (a/b) and (c/d).

To find LCM and HCF of (a/b) and (c/d) the generalized formula will be:

H.C.F = H.C.F of numerators / L.C.M of denominators

L.C.M = L.C.M of numerators / H.C.F of denominators

Now L.C.M of two numbers is the smallest number (not zero) that is a multiple of both.

H.C.F of two numbers is the largest whole number which is a factor of both.

Let’s take example of (4/5) & (3/7):

LCM=lcm of (4,3)/hcf of (5,7) = 12/1 = 12(Since 12 is the least number that comes in table of both 4,3 and 1 is the greatest number that can divide both 5,7).

HCF=hcf of (4,3)/lcm of (5,7) = 1/35 (Since 1 is the greatest number that can divide both 4,3 and 35 is the smallest number that comes in table of both 5,7).