Question

In a class 60% student pass in hindi and 45% in sanskrit. 25% studnet pass in both subject. How many student fail in both subject

Answer 1

let total student = 100
Hindi =60%
english =45%
At least one sub =25%
pass student = 60+45-25
=105-25
=80
fail student = 100 -80
=20%

Answer 2

let u denote universal set
let h be hindi
let S be sanskrit
now,
according to question,
n(u)=100%
n(h)=60%
n(S)=45%
n(hnS)=25%
now,
n(u)=n(h) +n(S)-n(hnS)+n(huS)compliment
100=60+45-25+n(huS)compliment
100=80+n(huS)compliment
20=n(huS)compliment