A three-person committee must be chosen from a group of 7 professors and 10 graduate students. If at least one of the people on the committee must be a professor, how many different groups of people could be chosen for the committee?
Choose the correct option:
A) 70 B) 560 C) 630 D) 1,260 E) 1,980
Total number of ways to select at least one professor = Number of ways to select 3 people from 10 students and 7 professors - Number of ways to select 3 people from 10 student (i.e. without including any professor)   = 17C3 - 10C3 = 680 - 120= 
<gadget id="calculator">680 - 120</gadget>
<output>560</output>
560   ANSWER:560
<result>B</result>
A three-person committee must be chosen from a group of 7 professors and 10 graduate students. If at least one of the people on the committee must be a professor, how many different groups of people could be chosen for the committee?