Question
Wed November 21, 2012 By: Shubham Deshpande

in a city,only two newspapers are published,they are newspaper A and B.it is known that,25%of population reads A.while20% of population reads B.and 8% of population reads both A&B.it is also known that 30% of population who reads A but not B looks into advertisements.40% of those who reads B but not A looks into advertisements.while 50% of those who read both look into ad.s.what is the percentage of population who read an ad???

Expert Reply
Mon November 26, 2012
let total population be 100X.
total population reading A= 25% of 100X= 25X
total population reading B=20% of 100X=20X
total population reading both=8% of 100X=8X
total population reading A but not B=25X - 8X=17X
total population reading B but not A=20X - 8X=12X
 
Total population reading an ad=30% of 17X + 40% of 12X + 50% of 8X=5.1X+4.8X+4X =13.9X
 
there for total % readind ad=(13.9X/100X)*100 = 13.9%
Home Work Help