2. Out of a group of 1000 people, 560 have a TV, 250 have a computer and 130 have both.
Find the number of people who have
(i) only a TV
(ii) only a computer
(iii) either a TV or a computer or both (iv) neither a TV nor a computer.
please help!
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- Let the group of people be S
Therefore,
n(S)=1000
Let the group of people having Tv be T
Therefore,
n(T)=560
Let the group of people having computer be C
Therefore,
n(C)=250
There are 130 people people having both computer and TV
Therefore,
n(TnC)=130
- 1.People having only TV.
n(T)=n(T)-n(TnC)
= 560-130
=430
- 2.People having only computer
n(C)=n(C)-n(TnC)
=250-130
=120
- 3.People having either a TV or a computer or both
Let this set be n(TuC)
n(TuC)=n(T)+n(C)-n(TnC)
=560+250-130
=810-130
- =790---------(1)
4.People not having neither a TV nor a computer.
n(TnC)'=1000-[n(T)+n(C)-n(TnC)
=1000-790-----(from 1)
=210
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