The sum of two numbers is 51 and the difference is 9. What are the numbers?
2 answers:
we dont know what is the two numbers so let us assume that one is x and other is y
so the sum of two numbers will be x+y which is equal to 51
and their difference is 9
so now we have two equations we can solve this by elimination method.
we know that we have -y and +y which is same value with opposite sign so we can cancel it and x+x will be 2x and 51+9=60
we can plug x=30 in any one of the equations
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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)
So, What percent of the college graduates donated to none of the three listed causes?
Percentage would be
(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
Hence, a) 11.26% and b) 50.23%