Relation L(p,q) is stored in 100 blocks, with 50 records ( or tuples ) of L fitting in one block .
L has total 100 blocks , each block have 50 tuples so total number of tuples in L = 100 * 50 = 5,000
50 tuples store in 1 block .
then 1 tuple store in (1/50) block , this is one single tuple size.
Similarly for K ,
K(m,n) is stored in 200 blocks with 100 records per block.
total number of tuples in K = 200 * 100 = 2,0000 tuples.
100 tuple store in 1 block
1 tuple store in (1/100) block . Each tuple size = (1/100) block
Now, it says , in conditional join , each tuple of L joins with five tuples of K .
So total number of tuples in join is = 5000 * 5 = 25000 tuples
Conditional join return all columns of L and K , that is it returns ( p,q,m,n )
Total size of each tuple size of join = each tuple size of L + each tuple size of K
= (1/50) + (1/100)
= (3/100) of a block
There are total 25000 tuples in join .
Total number of blocks require
= total number of tuples * size of each tuple
= 25000 * (3/100 )
= 250 * 3
= 750 blocks