Problem Solving (PS) | Re: A farmer is planting a row consisting of 4 unique apple trees and 4 un

Let the unique Apple trees be A1, A2, A3 and A4
Similary, unique Orange Trees be O1,O2,O3 and O4

Condition: No Apple or orange trees should be adjacent to each other.

Two arrangements are possible:-

Case1:

_A1_A2_A3_A4 (_ represents orange trees)

Apple trees can arrange themselves in 4! way since all are unique and order matters.
Similarly, Orange trees can arrange in 4! ways.

number of arrangements: 4! * 4! = 576

Case2:

A1_A2_A3_A4_

number of arrangements: 4! * 4! = 576

Total number
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