Newspaper mania

Let total people in town be denoted by $x$ . Then $x =50000$ .

People who read newspaper:
Nanjing morning: $a+b =28000$
Nanjing evening $b+c =23000$
People who read both $b= 4000$
People who read neither of them: $x-(a+b+c) = \boxed{ 3000}$ .

Draw a Venn Diagram, then it's so easy.

Let A = 28000,B=23000. A & B common People are 4000, let C = 4000, so total people is total People = (A+B)-C.totalPeople = 51000-4000=47000.

We know that total people in town is 50000 so we have left 3000 to reach total people. So the answer is 3000.

From the Venn Diagram above, the number of people who read neither is

$50000-19000-4000-24000=$ $\boxed{3000}$

28k + 23k = 51k 51k - 4k = 47k 50k-47k = 3k

:))

People who read the first newspaper = 28000 People who read the second newspaper = 23000 Let people who read first only as 28000-x (in which x is the number of people out of the 28000 who read both) Let people who read second only as 23000-y (in which y is the number of people out of the 23000 who read both) So x+y=4000 By adding both we get the total number of people who read any of the two newspapers: 28000-x+23000-y Since x+y=4000 Therefore x= 4000-y By substituting: 28000-(4000-y)+23000-y 28000-4000+y+23000-y 28000-4000+23000=47000 Since total number of people in the city =50000 Therefore number of people who read neither = 50000-47000=3000

50,000-4,000 is the number of people who don't read both news. The total number of people who read at least one type of news is (28,000+23,000)-4000. We subtract 4000 because that gets rid of the people who read both types of news. Now we are left with 47,000, which is the number of people who read either types of news, or both. So the people who read neither will be 50,0000 (total population) - 47,000 (The number of people who read at least one of the magazines.

I attacked this problem by using Venn Diagram.

Apply Inclusion-Exclusion Principle, i.e., 28000+23000-4000=47000. Then subtract 47000 to 50000 to get the number of people who neither read those newspapers.

Thus, the answer is 3000.

50000-(28000+23000-4000)=3000

Since 4000 did read both out of 50,000 ,so 46,000 did not read papers,Now, 22,000 ( 50,000-28,000)and 27,000 ( 50,000-23,000)did not read NanJing morning and Nanjing Evening news. Therefore 22,000 +27,000 =49,000 did not read papers and 49,000 -46,000 =3000 people read neighter Ans. K.K.GARG,India