Workers
Probability
Level
2
At a construction site, Jorge is in charge of hiring skilled workers for the project. Out of 80 candidates that he interviewed, he found that
- 45 were painters,
- 50 were electricians,
- 50 were plumbers,
- 15 had skills in all three areas, and
- all of them had skills in at least one of these areas.
If he hired everyone who was skilled in exactly 2 areas, how many candidates were hired?
by
Victor Paes Plinio