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)	Choose the correct choice from the following answers
A) 10 B) 14 C) 15 D) 16 E) 30
There are 4 letter without t: x, y, z, and w, so:   C14+C24+C34+C44=4+6+4+1= 
<gadget id="calculator">4+6+4+1</gadget>
<output>15</output>
15   Any letter (x, y, z, w) can be included or not. So, we have 2^4 combinations - 1 empty combination= 15 combinations   Answer: 15
<result>C</result>
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)