Browse · harp
Printsmc
counting and probability senior
Problem
How many arrays whose entries are s and s are there such that the row sums (the sum of the entries in each row) are and in some order, and the column sums (the sum of the entries in each column) are also and in some order? For example, the array satisfies the condition.
(A)
(B)
(C)
(D)
Solution
Note that the arrays and the sum configurations have one-to-one correspondence. Furthermore, the row sum configuration and the column sum configuration are independent of each other. Therefore, the answer is
Final answer
D