Puzzles/Logic puzzles/Pizzas/Solution

Puzzles | Logic puzzles | Pizzas | Solution

Aaron - green pepper, onions and sausage

Betty - green pepper, mushrooms and onions

Charlie - mushrooms, pepperoni and sausage

Debbie - green pepper, pepperoni and sausage

Eric - mushrooms, onions and pepperoni

Reasoning
We are informed that B and D had green pepper, B and C had mushrooms, D and E had pepperoni and A and C had sausage, all marked with a Y.

| A | B | C | D | E Green Pep |   | Y |   | Y | Mushrooms |  | Y | Y |   | Onions   |   |   |   |   | Pepperoni |  |   |   | Y | Y  Sausage   | Y |   | Y |   |

We are also informed that the pairs B and D, B and C, D and E, and A and C, didn't share anything, except what is already marked with a Y. This eliminates the possibilities marked with an N.

| A | B | C | D | E Green Pep |   | Y | N | Y | N  Mushrooms | N | Y | Y | N | Onions   |   |   |   |   | Pepperoni |  | N |   | Y | Y  Sausage   | Y | N | Y |   |

Knowing everyone had 3 toppings allows us to place another Y.

| A | B | C | D | E Green Pep |   | Y | N | Y | N  Mushrooms | N | Y | Y | N | Onions   |   | Y |   |   | Pepperoni |  | N |   | Y | Y  Sausage   | Y | N | Y |   |

And we know B didn't share with C or D.

| A | B | C | D | E Green Pep |   | Y | N | Y | N  Mushrooms | N | Y | Y | N | Onions   |   | Y | N | N | Pepperoni |  | N |   | Y | Y  Sausage   | Y | N | Y |   |

Allowing us to place 2 more Ys.

| A | B | C | D | E Green Pep |   | Y | N | Y | N  Mushrooms | N | Y | Y | N | Onions   |   | Y | N | N | Pepperoni |  | N | Y | Y | Y  Sausage   | Y | N | Y | Y |

D didn't share with E, A didn't share with C.

| A | B | C | D | E Green Pep |   | Y | N | Y | N  Mushrooms | N | Y | Y | N | Onions   |   | Y | N | N | Pepperoni | N | N | Y | Y | Y Sausage   | Y | N | Y | Y | N

This allows us to place the remaining 4 Ys.

| A | B | C | D | E Green Pep | Y | Y | N | Y | N  Mushrooms | N | Y | Y | N | Y  Onions    | Y | Y | N | N | Y  Pepperoni | N | N | Y | Y | Y  Sausage   | Y | N | Y | Y | N

Surprisingly, no one chose green pepper, onions and pepperoni.