Saved Bookmarks
| 1. |
Let X = {n ∈ N : 1 ≤ n ≤ 50}. IfA = {n ∈ X : n is multiple of 2} andB = {n ∈ X : n is a multiple of 7}, then the number of elements in the smallest subset of X containing both A and B is_____ |
|
Answer» n(A) = 25 n(B) = 7 n(A ∩ B) = 3 n(A ∪ B) = 25 + 7 - 3 = 29 n(A ∪ B) = n(A) + n(B) – n(A ∩ B) = 25 + 7 – 3 = 29 |
|