of 45 applicants for a job , 21 had at least 4 years ' experience , 27 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 ?
"45 - 5 = 40 40 - 21 - 27 = - 8 then 8 are in the intersection between 4 years experience and degree . answer : b"
add(subtract(add(21, 27), subtract(45, 5)), subtract(27, 21))