What you’ll learn2 learning objectivesChoose one objective for a focused lesson, or study the complete topic.5.2.1Permutations and combinations• understand the terms permutation and combination, and solve simple problems involving selectionsSyllabus objective5.2.2Arrangement restrictions• solve problems about arrangements of objects in a line, including those involving - repetition (e.g. the number of ways of arranging the letters of the word 'NEEDLESS') - restriction (e.g. the number of ways several people can stand in a line if two particular people must, or must not, stand next to each other). Questions may include cases such as people sitting in two (or more) rows. Questions about objects arranged in a circle will not be included.Syllabus objective