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plzz solve question 28 to 30
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Dear student,



Let A denote the set of persons who read newspaper A.Let B denote the set of persons who read newspaper B.Let C denote the set of persons who read newspaper C.Now according to question, a+d+e+g=26      ....1b+d+f+g=25       ....2c+e+f+g=14        ....3d+g=11                   ....4f+g=10                     ....5e+g=9                       .....6It is given that c=0from eq3 and 6, we havef=5from eq(5), f+g=10 ⇒ 5+ g = 10⇒ g = 5from eq(6), e+g = 9 ⇒ e+5 = 9⇒ e=4from eq(4), d+g = 11 ⇒ d+5 = 11⇒ d=6from eq(2), b+d+f+g = 25 ⇒ b+6+5+5 = 25 ⇒ b=9from eq(1), a+d+e+g = 26 ⇒ a+6+4+5 = 26⇒ a =11i.e, a=11,b=9,c=0,d=6,e=4, f=5 and g =5Ques 28. The percentage of readers who read all the three newspapers,n(A ∩ B ∩ C)=g=5Ques 29. The percentage of readers who read A and B but not C, n(A ∩ B ∩C')=d=6Ques 30. The percentage of readers who read atleast one of the three newspapers, nA∪B∪C = a+b+c+d+e+f+g=11+9+0+6+4+5+5=40
Regards

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Let n(A only) =a, n(B only) =b, n(C only)= c , n(A nd B only) = d, n( A and C only) =e , n(B and C only)= f
and n(A and B and C) = g
This gives, a+e+g+d=26 , b+d+g+f=25 and c+e+g+f=14 But, c=0 Therefore, e+g+f=14
Also, d+g = 11, g+f=10 and e+g= 9 
This gives, a=11, b= 9, c=0, d=6, e=4, f=5 and g=5
Hence, for Q.1 The correct ans. is 5
For Q.2 the correct ans. is 6 and for Q.3 the correct ans. is 40
 
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