For i = 1, 2, 3, 4, let Ti denote the event that the students Si and Si+1 do NOT sit adjacent to each other

Question

PARAGRAPH “A”

There are five students S₁, S₂, S₃, S₄ and S₅ in a music class and for them there are five seats R₁, R₂, R₃, R₄ and R₅ arranged in a row, where initially the seat R_i is allotted to the student S_i, i = 1, 2, 3, 4, 5. But, on the examination day, the five students are randomly allotted the five seats.

For i = 1, 2, 3, 4, let T_i denote the event that the students S_i and S_i+1 do NOT sit adjacent to each other on the day of the examination. Then, the probability of the event T_{1 ∩} T_{2 ∩} T₃ ∩ T₄ is

(A) 1/15  (B)1/10  (C) 7/60   (D) 1/5

Answer 1

Answer:C

Solution:

Same number of ways in reverse order​