pq= 313.177 --> 313
We know that our Population X is 653 individuals. Of this population 104 have floppy ears (Xf). We know that p (short) is dominant over q (floppy).
Basic equations for Hardy Weinberg:
p + q = 1
Taking the square root of this number gives us the frequency
Now we can enter this into p+q=1
This means that p= 1 - q which solves to 0.6001
Now that we now both p and q we can start calculating the frequencies of the genotypes
2pq gives 2 * 0.6001 * 0.399 = 313.177 which gets rounded up to 313
To find the frequency of each genotype we divide the total population by each genotypes' population.