Homework Statement
How many combinations of people are there if you choose 4 or 5 from a group of 10?
Homework Equations
Relies on binomials
The Attempt at a Solution
binomial (10,4) = binomial (10,6) = 210
But when choosing 5 the answer is binomial (10,5) / 2 = 126
Why do I need to divide by 2?
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