pradeepkaushal9518 wrote:Of the 500 business people surveyed, 78 percent said that they use their laptop computers at home, 65 percent said that they use them in hotels, and 52 percent said that they use them both at home and in hotels. How many of the business people surveyed said that they do not use their laptop computers either at home or in hotels?

i dont have option but answer

Venn diagram with sample space 500 and having two intersecting sets A (at home) and B (in hotels), such that n (A) = 390, n (B) = 325, and n (A∩B) = 260, is to play role here, and we have to answer n (A ∪ B)'. Remember, n (A ∪ B)' = n (sample space) - n (A ∪ B), and n (A ∪ B) = n (A) + n (B) - n (A∩B) = 390 + 325 - 260 = 455, and hence n (A ∪ B)' = [spoiler]500 - 455 = 45[/spoiler].

Of the 500 business people surveyed, 78 percent said that they use their laptop computers at home, 65 percent said that they use them in hotels, and 52 percent said that they use them both at home and in hotels. How many of the business people surveyed said that they do not use their laptop computers either at home or in hotels?

i dont have option but answer

Let's say number is X
then X + 0.78 T + 0.65T - 0.52T = T ( T == total =500)
X = 0.09T = 0.09 * 500 = 45

thnaks buddies for your answer its 45 only

pradeepkaushal9518 wrote:Of the 500 business people surveyed, 78 percent said that they use their laptop computers at home, 65 percent said that they use them in hotels, and 52 percent said that they use them both at home and in hotels. How many of the business people surveyed said that they do not use their laptop computers either at home or in hotels?

i dont have option but answer

people using laptop at home = 0.78 x 500 = 390
people using laptop in hotels = 0.65 x 500 = 325
people using laptop both at home and in hotels = 0.52 x 500 = 260
let people who do not use their laptop = x
390 + 325 - 260 + x = 500 --> x= 500+260 - 715 = 760 -715 = 45 Ans.