[size=150]Permutations and combinations are both concepts in combinatorial mathematics that deal with counting and arranging objects. However, they differ in how they handle the arrangement or selection of objects.[br][br]Permutations:[br]Permutations refer to the arrangement of objects in a particular order. In a permutation, the order or sequence of objects is important. For example, consider a set of objects A, B, and C. The permutations of these objects would include arrangements like ABC, BCA, CAB, etc. The number of permutations can be calculated using the formula:[br][br]nPr = n! / (n - r)![br][br]where n is the total number of objects and r is the number of objects being selected or arranged.[br][br]Combinations:[br]Combinations, on the other hand, refer to the selection of objects without considering their order. In a combination, the order of objects is not important. For example, using the same set of objects A, B, and C, the combinations would include selections like AB, AC, BC, etc. The number of combinations can be calculated using the formula:[br][br]nCr = n! / (r! * (n - r)!)[br][br]where n is the total number of objects and r is the number of objects being selected.[br][br]In summary, permutations focus on the arrangement of objects in a specific order, while combinations focus on the selection of objects without regard to their order.[/size]