Question

if you have in class of 26 students ,15 of them like maths ,13 of them like english and 9 of them don't like maths or english .
find the probability that a student chosen at random likes english but no maths .​

Answer 1

Total number of students = 26

Students likes maths = 15

Students likes English = 13

Students likes neither maths nor English = 9

Total resultant number of interest of maths and English,

= 26 - 9 = 17

Now students likes both the subjects Maths and English,

$17 = 15 + 13 - x \\ x = 28 - 17 = 11$

Students likes english but no maths,

$= 13 - 11 = 2$

Probability that a student chosen at random likes english but no maths

$p = \frac{2}{26} = \frac{1}{13}$