In a group of 3 boys and 7 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be selected?  Choose the correct choice from the following choices
A) 145	B) 175	C) 205	D) 235	E) 265
Number of ways to select four children is 10C4 = 210   Number of ways to choose only girls is 7C4 = 35   Number of ways that at least one boy is selected is  210 - 35= 
<gadget id="calculator"> 210 - 35</gadget>
<output>175</output>
175   The answer is 175.
<result>B</result>
In a group of 3 boys and 7 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be selected?