Of 30 applicants for a job, 16 had at least 4 years' experience, 21 had degrees, and 5 had less than 4 years' experience and did not have a degree. How many of the applicants had at least 4 years' experience and a degree?  Options
A) 12	B) 10	C) 9	D) 7	E) 5
set 12 : people with more than 4 years exp   set B : people with degree   12UB = total - (less than 4 exp and no degree)   12UB = 30-5= 
<gadget id="calculator">30-5</gadget>
<output>25</output>
25   12UB= 12 + B - 12iB   12iB = 21+16-25= 
<gadget id="calculator">21+16-25</gadget>
<output>12</output>
12   12nswer 12
<result>A</result>
Of 30 applicants for a job, 16 had at least 4 years' experience, 21 had degrees, and 5 had less than 4 years' experience and did not have a degree. How many of the applicants had at least 4 years' experience and a degree?