Question

I have been trying to figure this out for day's please help if you can.

A survey of 59 customers was taken at a book store regarding the type of novels purchased. The survey found 34 customers purchased mysteries, 27 purchased science fiction, 20 purchased romance novels, 13 purchased mysteries and science fiction, 10 purchased mysteries and romance novels, 7 purchased science fiction and romance novels, and 3 purchased all types.

A) How many purchased mysteries and science fiction, but not romance?

B)How many purchased mysteries or science fiction?

C) How many purchase exactly 2 types?

Answer 1

Just draw a Venn diagram. There are 3 regions, we'll call them m,s,r, with overlapping regions labeled, ms,mr,rs,mrs.

Now start filling them in, from the inside out

mrs = 3
rs = 7-3 = 4
mr = 10-3 = 7
ms = 13-3 = 10
m = 34-(3+7+10) = 21
r = 20-(3+4+7) = 6
s = 27-(3+4+10) = 10

Now you can answer the questions