Question

this is que of ncert 11 maths pg no 25 plz ans of this que its urgently​

Answer 1

Let F,B,C be the sets of students who received medals in football, basketball, and cricket respectively.

n(F)=38

n(B)=15

n(C)=20

n(F∪B∪C)=58

n(F∩B∩C)=3

We know, n(F∪B∪C)=n(F)+n(B)+n(C)−n(F∩B)−n(B∩C)−n(F∩C)+n(F∩B∩C)

n(F∩B)+n(B∩C)+n(C∩F)=73−58+3=18

Let F,B,C be the sets of students who received medals in football, basketball, and cricket respectively.

n(F)=38

n(B)=15

n(C)=20

n(F∪B∪C)=58

n(F∩B∩C)=3

We know, n(F∪B∪C)=n(F)+n(B)+n(C)−n(F∩B)−n(B∩C)−n(F∩C)+n(F∩B∩C)

n(F∩B)+n(B∩C)+n(C∩F)=73−58+3=

the number of students who received medals in exactly two of the three

sports is,

n(F∩B)+n(B∩C)+n(C∩F)−3× number of students who received medals in exactly two of the three

sports is,

n(F∩B)+n(B∩C)+n(C∩F)−