Of the given numbers
(i) √27
(ii) √256
(iii) 0.3796
(iv) 7.478478...
(v) 1.101001000100001...
(i) and (v) are irrational
(i) The decimal expansion of √27 is non-terminating non-recurring, therfore it is an irrational number.
(ii) √256 =16 This is a rational number as it can be represented in p/q form.
(iii) 0.3796is terminating decimal expansion , therefore, it is a rational number.
(iv) 7.478478…. this decimal expansion is non-terminating recurring, therefore, it is a rational number.
(v) 1.101001000100001…is non-terminating non-repeating decimal expansion, therefore, it is an irrational number.
So, (i) and (v) are irrational