Paper 2 · November 2018 · permutations and combinations

When selecting a number of objects from a set, which condition makes the selection a permutation rather than a combination?

AWhen the order in which the objects are selected matters.

BWhen the order in which the objects are selected does not matter.

CWhen each object can be selected more than once in the same selection.

DWhen the objects being selected are indistinguishable from one another.

Explanation

A permutation is an ordered arrangement, so two selections containing the same objects in a different order count as different permutations. A combination ignores order, which is why it does not.

Derived from ZIMSEC Statistics Paper 2, November 2018, Q2

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