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Find number of people
If there are some people, out of which 40% drink coffee, 40% drink tea, 50% drink milk, 10% drink all the three, 20% drink both coffee and tea, 20% drink both tea and milk, 20% drink both milk and coffee and 10 people wont drink any of the three. so find out how any people were there actually?
praveenbiggod
- Dec 9th, 2010
t=Tea
c=Coffee
m=Milk
n=Number of persons
n(c or t or m)=n(c) +n(t) +n(m)-n(c &t)-n(t & m)- n(m & c) +n(c & t & m)
40+40+50-20-20-20+10=80
number of persons drink=80
No. of people wont drink any of them=10
but they are asking number of persons so i.e = 80+10=90
