Let a = 0.5 = 0.50
And, b = 0.55
We observe that in the second decimal place a has digit 0 and b has digit 5. Therefore a < b. So, if we consider irrational numbers
x = 0.51051005100051…
y = 0.5305343055353530…
We find that,
a < x < y < b
Hence, x and y are required irrational numbers.