When you add (2),(3), and (4), shouldn't there be a total of 3x as each equation has one x variable?
Also, can you look at my post and advice the reason that the formula, which is correct, is not working?
nislamA certain company with 118 employees offered three different training courses, one in CPR, one in spreadsheet skills, and one in touch-typing. Each employee was required to take at least two of these courses, and some employees took all three of the courses.
If 71 employees took the CPR course, 102 employees took the spreadsheet skills course, and 89 employees took the touch-typing course, how many employees took all three courses?
Attachment:
Screenshot 2024-10-03 at 11.35.10 AM.png
A + B + C + x = 118 (1)
A + B + x = 71 (2)
A + C + x = 102 (3)
B + C + x = 89 (4)
(2) + (3) + (4)
2(A+B+C+x) + x = 71 + 102 + 89 = 262
2*118 + x = 236 + x = 262
x = 262 - 236 = 26
26 employees took all three courses.
IMO B