deadmank2s wrote:Foodmart customers regularly buy at least one of the following products: milk, chicken, or apples. 60% of shoppers buy milk, 50% buy chicken, and 35% buy apples. If 10% of the customers buy all 3 products, what percentage of Foodmart customers purchase 2 of the above products?
a) 5%
b) 10%
c) 15%
d) 25%
e) 30%
You can draw a Venn diagram. 3 Intersecting circles!
Say Milk alone buyers = a;
Chicken alone buyers = b;
Apple alone buyers = c;
Milk & Chicken buyers = x;
Milk & Apple buyers = y;
Apple & Chicken buyers = z;
All 3 buyers = 10%; Given.
As total no. of buyers are 100% then, we can write...
100 = a+b+c+x+y+z+10; =>
(a+b+c)+(x+y+z) = 90 ..........(1)
Again, we can write...
a+x+y+10 = 60 => a+x+y = 50..........(2)
b+x+z+10 = 50 => b+x+z = 40..........(3)
c+z+y+10 = 35 => c+z+y = 25..........(4)
Adding eqn. 2,3, & 4 we get...(a+b+c)+2.(x+y+z) = 115 ..........(5)
By subtracting Eqn. 5 from Eqn 1, we get...
x+y+z = 25. Ans
D.