In a class total 34 students, 16 are have a brother, 15 are have sisters, 9 students don't have either brothers or sisters.Find the number of students having both brother and sisters.

• Total Number of students = 34
  Let A be the Number of students have a brothers.
  Let B be the number of students have a sisters.
  AUB = Number of students have either brothers or sisters=34-9=25
  n(AUB)= n(A)+n(B)-n(AnB)
  25=16+15-n(AnB)
  n(AnB)=31-25
  n(AnB)=6
  The number of students having both brother and sisters = 6
• 12 years agoHelpfull: Yes(33) No(1)
• Total no. of students=34
  Students having atleast 1 brother or sister=34-9=25
  Total no. of students having both brother and sisters=(16+15)-25=31-25=6
• 8 years agoHelpfull: Yes(4) No(0)