Question

In a survey there are 120 participants, 80 are from group A, and 21 are in both (A and B). How many participants are in B group?

Answer 1

Here we have given n(AUB) = 120 ACA) = 80 A DCA OB) = 21 & we have to calculate n (B) = ? we know that A(AUB) = n(A) + n(B) - DCAMB) 120 80+ n(o)-21 120-80 = n(B)- 21 120-80 = n(B)-21 40+21= n(B) | n(B) = 61participants are in group B :

Here we have given In(AUB)= 1201 n(A) = 80 NCAAB) = 21 & we have to calculate 2(B) = ? we know that n (AUB) = n(A) + n(B) = n(ADB) 120 - 80+ n(B)- 2) 120- 80= n(B) - 21 40 = n(B) - 25 40+21= n(B) (B) = 6 61 participants are in group B