The Logic Zone

There are two common methods of solving logic problems. This page gives an example of a logic problem being worked out using the "table" or "fill-out grid" method. The other method can be called "ABC grid", "crosshatch grid" or simply "the grid method". For an example of this puzzle worked out using the grid method, click here.

Name	Surname	House No.	Dog

Three people live in Hopper St. Can you sort out their names, house numbers & their dogs names?

Dogs: Bob, Patch, Toby

Names: Jim, Dick & Mike

Surnames: Black, Turnip & Spade

House No.s: 1,2,3

Clue 1. Dick lives at a higher number than Mr. Spade; neither of these own Bob.

Clue 2. Toby lives at No. 1

Clue 3. Jim Black does not live at No. 3

Clue 1 tells us that Dick, Mr Spade and Bob have no association with each other. We can therefore fill the table out with these 3 details:

Name	Surname	House No.	Dog
Dick
	Spade
			Bob

Clue 3 tells us that Jim Black does not live at No. 3. There is only space for this person to fit in the table with Bob the dog:

Name	Surname	House No.	Dog
Dick
	Spade
Jim	Black		Bob

As there is only one space left in both the name and surname columns, we can now fill these in:

Name	Surname	House No.	Dog
Dick	Turnip
Mike	Spade
Jim	Black		Bob

Clue 3 tells us that either Dick or Mr. Spade lives at No. 3. Clue 1 tells us that Dick lives at a higher number than Mr. Spade and therefore:

Name	Surname	House No.	Dog
Dick	Turnip	3
Mike	Spade
Jim	Black		Bob

Back to clue 2: Toby lives at No. 1. There is only one place this can fit:

Name	Surname	House No.	Dog
Dick	Turnip	3
Mike	Spade	1	Toby
Jim	Black		Bob

The table can now be completed:

Name	Surname	House No.	Dog
Dick	Turnip	3	Patch
Mike	Spade	1	Toby
Jim	Black	2	Bob

I hope the above makes sense to you all.

Any further questions or comments, please email The Logic Zone.