8. In a club of 250 members, it is found that 130 of them drink tea and 85 of them drink tea but not coffee. If each of the members of the club drinks at least one of the items between tea and coffee, the find- (i) how many members drink coffee (ii) how many members drink coffee, but not tea? Advance Math Class 10 - Exercise 1.1:

In a club of 250 members, it is found that 130 of them drink tea and 85 of them drink tea but not coffee. If each of the members of the club drinks at least one of the items between tea and coffee, the find- (i) how many members drink coffee (ii) how many members drink coffee, but not tea?

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Solution:

Let the set of members drink tea be T and

The set of members drink coffee be C

Given,

 

 n(TUC)= 250,

 n(T – C)= 85

(i) The number of members who drink coffee

n(C)= n(TUC) – n(T – C)

       = 250 – 85

       = 165

(ii) n(TꓵC)= n(T) + n(C) – n(TUC)

= 130 + 165 – 250

=45

Therefore, number of members drink coffee, but not tea,

n(C – T)= n(C) – n(TꓵC)

             = 165 – 45

             = 120

  Exercise: 1.1  

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