The music class consists of 4 girls and 7 boys. How many ways can a group of 3 be formed if it has to include at least one boy?
Choices.
A) 155  B) 158  C) 161  D) 165  E) 172
161lassic combination problem   At least 1 boy = Total - all girls   All girls = 161(4,3) = 4   Total combination = 161(11,3) = 165   Ans = 165-4= 
<gadget id="calculator">165-4</gadget>
<output>161</output>
161   ANS:161
<result>C</result>
The music class consists of 4 girls and 7 boys. How many ways can a group of 3 be formed if it has to include at least one boy?