n(A ∪ B)= n(A)+ n(B)- n(A ∩ B)
Practical Problems on Union and Intersection of Three Sets
n(A ∪ B ∪ C)= n(A) +n(B)+ n(C)- n(A ∩ B)- n(B ∩ C)- n(C ∩ A)+ n(A ∩ B ∩ C)
Shaalaa.com | Practical Problems on Union and Intersection of Sets
In a committee, 50 people speak French, 20 speak Spanish and 10 speak both Spanish and French. How many speak at least one of these two languages?
If X and Y are two sets such that X ∪Y has 18 elements, X has 8 elements and Y has 15 elements; how many elements does X ∩Y have?
In a group of students 100 students know Hindi, 50 know English and 25 know both. Each of the students knows either Hindi or English. How many students are there in the group?
If S and T Are Two Sets Such that S Has 21 Elements, T Has 32 Elements, and S ∩ T Has 11 Elements, How Many Elements Does S ∪ T Have?
In a group of 70 people, 37 like coffee, 52 like tea, and each person likes at least one of the two drinks. How many people like both coffee and tea?