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From the set of numbers x, y, t, z and w, how many different [#permalink]
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19 Jun 2010, 14:48
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From the set of numbers x, y, t, z and w, how many different combinations can we have without the t in them? Ex:. (x,y), (x), (w,z,y,x), etc and (x,y)=(y,x) A. 10 B. 14 C. 15 D. 16 E. 30
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Re: Combination problem [#permalink]
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19 Jun 2010, 14:59
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Gusano97 wrote: Could anybody help me with these problem?
From the set of numbers x, y, t, z and w, how many different combinations can we have without the t in them? Ex:. (x,y), (x), (w,z,y,x), etc and (x,y)=(y,x)
A)10 B)14 C)15 D)16 E)30 There are 4 letter without t: x, y, z, and w, so: \(C^1_4+C^2_4+C^3_4+C^4_4=4+6+4+1=15\) Answer: C.
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Re: Combination problem [#permalink]
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22 Jun 2010, 14:23
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Another way: Any letter (x, y, z, w) can be included or not. So, we have 2^4 combinations  1 empty combination = 15 combinations
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Re: From the set of numbers x, y, t, z and w, how many different [#permalink]
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22 Aug 2014, 03:08
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Re: From the set of numbers x, y, t, z and w, how many different [#permalink]
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10 Sep 2016, 04:31
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Re: From the set of numbers x, y, t, z and w, how many different [#permalink]
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10 Apr 2017, 16:09
Question is to find no of combinations of x,y,z,w Choosing only 1 letter  4C1 ways = 4 Choosing only 2 letter  4C2 ways = 6 Choosing only 3 letter  4C3 ways = 4 Choosing only 4 letter  4C4 ways = 1 Total possible combinations = 4+6+4+1 = 15
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Re: From the set of numbers x, y, t, z and w, how many different
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