Half the challenge in combination and permutation questions is identifying whether it is a combination or permutation. Being able to quickly distinguish the two is critical to a high score.
Here are some clues to look for.
Does order matter?
Does it matter if the items’ order or positions are changed? If so, it is a permutations problem; if not, it is a combinations problem.
Which words are used?
The exact terms “permutations” or combinations” will rarely be used on the GMAT.
Some words or phrases that indicate permutations include:
arrange in a row, winning, letters, security codes, choosing in order, and choosing with/without replacement.
Some words or phrases that indicate combinations include:
handshakes, food, choosing from multiple groups, and choosing more than one person at the same time (such as friends or a team).