11 C 4; First take the first number, 11, and subtract the second to get 7. In combinations you use factorials, here it would be 11! / 7! 4!. then divide it out and multiply, by taking the 7! and crossing out the numbers written out on the top helped to make this easier with out a calculator.
it would look like 11*10*9*8 / 4*3*2 = 330