MathDB
COMC 2011 Problem 8

Source:

November 4, 2012
calculusintegration

Problem Statement

A group of n  friends wrote a math contest consisting of eight short-answer problem S1,S2,S3,S4,S5,S6,S7,S8S_1, S_2, S_3, S_4, S_5, S_6, S_7, S_8, and four full-solution problems F1,F2,F3,F4F_1, F_2, F_3, F_4. Each person in the group correctly solved exactly 11 of the 12 problems. We create an 8 x 4 table. Inside the square located in the iith row and jjth column, we write down the number of people who correctly solved both problem SiS_i and FjF_j. If the 32 entries in the table sum to 256, what is the value of n?