UPSC Prelims 2022 · CSAT (Paper 2) · Q77
Logical Reasoning & Analytical Ability
Hard · Arrangement combinatorics
There are 9 cups placed on a table arranged in an equal number of rows and columns, out of which 5 cups contain tea and 4 cups contain coffee. In how many ways can they be arranged so that each row should contain at least one cup of tea?