Suppose A1, A2, A3, ..., A30 are thirty sets each having 5 elements with no common elements across the sets and B1, B2, ..., Bn are n sets each with 3 elements with no common elements across the sets. Let \(\rm \displaystyle\bigcup^{30}_{i = 1} A_i = \displaystyle\bigcup^n_{j = 1} B_j = S\) and each elements of S belongs to exactly 10 of the Ai's and exactly 9 of the Bj's. Then n is equal to

Suppose A1, A2, A3, ..., A30 are thirty sets each having 5 elements wi

1.	Suppose A1, A2, A3, ..., A30 are thirty sets each having 5 elements with no common elements across the sets and B1, B2, ..., Bn are n sets each with 3 elements with no common elements across the sets. Let \(\rm \displaystyle\bigcup^{30}_{i = 1} A_i = \displaystyle\bigcup^n_{j = 1} B_j = S\) and each elements of S belongs to exactly 10 of the Ai's and exactly 9 of the Bj's. Then n is equal to
A.	15
B.	30
C.	40
D.	45
Answer» E.