Out of 14 people,twelve said that it was not the case that they watched television but did not watched television but did not listen to radio.Also, for nine people, it is not the case that they did not watched television and do not listen to radio. Finally,seven people either watch television or radio but do not do both. Now let A be the number of people that listen radio. Find A and B.

twelve said that it was not the case that they watched television but did not listen to radio means n of A intersection B` of whole complement =12 for nine people, it is not the case that they did not watched television and do not listen to radio means number of A` intersection B` the whole complement =9seven people either watch television or radio but do not do both. Now let A be the number of people that listen radio means n of A Union B - n of A intersection B=7Now use de`morgans law to solve and put it in the third equation you will get answer 2