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TIMO 2018 - Senior Secondary (Grades 10-12) - Heat Round - Paper 4 Question 22

TIMO · TIMO 2018 - Senior Secondary (Grades 10-12) - Heat Round - Paper 4

Question 22

Five balls and five pockets are labelled $A,B,C,D,E$. Put one ball in each pocket at random. How many arrangements have exactly two balls matching their pocket's label?