There are 15 prime numbers in the first 50 integers i.e. 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43 and 47.
There are 12 integers are multiples of 4 i.e 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 an 48
∴ required probability= 15/50 + 12/50 = 27/50