venn diagrams......?

Question

suppose that a sample of 100 students were surveyed to find out which they read of the magazines times, newsweek and bulletin. it was found that
55 students read at least one of the above magazines.
28 read time,
26 read newsweek
14 read bulletin.
4 read both time and bulletin,
3 read both newsweek and bulletin and
2 read all three magazines.

How many students read newsweek but neither of the other 2?

there are 3 diffferent answers so far does anyone know which is correct
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Answer 1

If we let T, N and B be the sets of students that read time, newsweek and bulletin, respectively, and use #(S) to denote the number of elements of a given set S, then inclusion exclusion formula gives us that

#(T∪B) = #(T) + #(B) - #(T∩B) = 28 + 14 - 4 = 38.

Thus the number that read at least one of time or bulletin is 38. Then, since 55 read at least one paper, it follows that the number that read newsweek but neither of the other two is given by

#(T∪N∪B \ T∪B) = #(T∪N∪B) - #(T∪B) = 55 - 38 = 17.

Answer 2

B=Bulletin, T=Time, N=Newsweek

Let's look at B readers:

2 (those that read all 3)
2 (that read T also, but not N)
1 (that read N also, but not T)

That leaves 9 that read B only.

55 readers - 14 B = 41 , so
T only + N only + TN = 41

T only + TN = 28 - 4 = 24
N only + TN = 26 - 3 = 23
T + N + 2TN = 47
T + N + TN = 41

TN = 6
So N = 17

Answer 3

# TvNvB = #T+#N+#B -#T^N-#T^B-#B^N+#T^N^B
55 = 28+26+14-#T^N-4-3-2
T^N = 28+26+14-4-3-2-55 = 4
#N - #N^T-#N^B+#N^T^B = 26-4-3+2 = 21