Question 1163352
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C(6,3) is the number of ways of choosing 3 of the 6 toppings.<br>
3 is only the MAXIMUM allowed number of toppings; you can also have 2, or 1, or 0 toppings.  So the answer is<br>
C(6,3)+C(6,2)+C(6,1)+C(6,0)<br>