Skip to content / Đến nội dung
ThichHocToan.com

TIMO - 2018 - Grade 9 - Heat Round - Paper 4 Question 22

TIMO · TIMO - 2018 - Grade 9 - Heat Round - Paper 4

Question 22

There are 5 balls with labels A, B, C, D, E respectively and there are 5 pockets with labels A, B, C, D, E respectively. Each ball is put into one pocket randomly. Find the number of way(s) in which exactly 3 balls have labels matching the labels on the pockets.