Permutations and Combinations: Overview for GMAT Quant
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Hello, I have always had a tough time memorizing formulas for combinations, permutations, series, and sequences. I know they appear very rarely; however, I am trying to receive the best score possible. Is there some acronym or word association to best memorize them? Should I even bother "messing" with them since the ACT test is in two weeks? You're right that combination and permutation practice problems and series don't show up all that much on the ACT - as our complete guide to sequences on ACT Math points outthere is at most one sequence question per test.
In addition, many though not all ACT sequence questions can be answered without formulas, so if you have trouble memorizing formulas or worse, tend to memorize formulas combination and permutation practice problemsyou might want to steer clear of formula memorization and practice solving these kinds of questions longhand.
And combination and permutation practice problems with sequence questions, probability questions can often although not always be answered by plugging in answer choices or plugging in numbers. If you're worried that you won't be able to solve these kinds of questions without formulas or that it'll take too much timethen there are a variety of different methods you can use to memorize formulas.
Once you've memorized the formulas, be sure to practice using them in actual problems both to help you remember and to help you learn how to put them into use - otherwise, there's no point in memorizing them. I see no reason why you shouldn't continue to work on these types of problems in the short time you have before the ACT unless you have bigger issues on other parts of combination and permutation practice problems test that could cost you more points.
However, instead of just memorizing formulas, I'd focus on doing practice problems. Formulas will only get you so far if you don't really understand what's going on in the problem, and there are actually combination and permutation practice problems few formulas for these types of problems that are necessary on the ACT. Here are some resources I combination and permutation practice problems recommend for practice if you want to get a better handle on sequences, series, combinations, and permutations: PrepScholar article on sequences and series includes formulas, sample questions, tips, and practice.
ACT to add a line break simply add two spaces to where you would like the new line to be. Check out the FAQ! PrepScholar article on sequences and series includes formulas, sample questions, tips, and practice Varsity Tutors practice test for Permutations and Combinations Varsity Tutors practice problems for Sequences permanent link answered 28 Mar '16, Laura and Sam permanent link answered 28 Mar '16,