Answer: a) 11.26% and b) 50.23%
Step-by-step explanation:
Number of graduates donated to a political campaign n(A) = 91
Number of graduates donated to assist medical research n(B) = 76
Number of graduated to help preserve the environment n(C) = 131
Number of graduated donated to all n(A∩B∩C) = 27
Number of graduates donated to none = 24
Number of graduated donated to political campaign and to medical research n(A∩B) = 32
Number of graduates donated to medical research and to preserve the environment n(B∩C) = 48
Number of graduates donated to a political campaign and to preserve the environment n(C∩A) = 56
Now,
n(U)=n(A)+n(B)+n(C)-n(A∩B)-n(B∩C) -n(C∩A)+n(A∩B∩C)+n(none)
[tex]n(U)=91+76+131-32-48-56+27+24=213[/tex]
So, What percent of the college graduates donated to none of the three listed causes?
Percentage would be
[tex]\dfrac{24}{213}\times 100\\\\=11.26\%[/tex]
(b) What percent of the college graduates donated to exactly one of the three listed causes?
Exactly one = 91+76+131-2(32-56-48)+3(27)=107
Percentage would be
[tex]\dfrac{107}{213}\times 100\\\\=50.23\%[/tex]
Hence, a) 11.26% and b) 50.23%