If p and q are two consecutive natural numbers then commom factor of p and q is 1

So, HCF(p, q) = 1

Ex: Let the two consecutive natural numbers are 3 and 4

Now, 3 = 1 * 3

and 4 = 1 * 2 * 2

Now, HCF(3, 4) = 1           {since only 1 is common}