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Problem Solving Strategy
Problem Solving Strategy
A matrix is a two-dimensional chart that is used to organize information in a problem.
A matrix can use the process of elimination in a systematic way.
One way to improve your logical reasoning ability is to solve logic problems. The basic idea behind these problems is to solve them by matching items in various categories.
Most logic problems can be solved by using a chart or a table that we’ll call a matrix. Using a logic matrix sets up a one-to-one correspondence between elements in a problem.
Graph paper can make it easier to create/draw a matrix to work with.
Although you might tend to focus naturally on what must be true in a problem, it becomes even more important to pay attention to what isn’t possible when working with this problem solving strategy..
Matrix logic is a strategy based on things that cannot be.
One of the really successful actions of good problem solving is to read, re-read, and read the clues/problems over and over again and it is the very backbone of this problem-solving strategy.
Continually reviewing the clues gives your brain an opportunity to connect more and more information, eliminate more and more information, and reach a solution.
Enjoy the challenge and expand the thinking ability of your brain.
Dawn, Mark, Josh and Tina are friends. They each have a nickname. Their nicknames are Spider, Curly, Ace and
Fudgy, but not in that order. What is the nickname of each of the friends? Clues
Josh plays tennis with Curly and goes swimming with Ace.
Tina has been on holiday with Curly but travels to school with Fudgy.
Spider, Curly and Dawn play in the football team.
Spider sometimes goes to tea with Josh.
Spider Curly Ace Fudgy
Dawn
Mark
Josh
Tina
What does this tell us about Josh?• It tells us that Josh cannot be
the same person as Curly or Ace, if he does activities with both of them
• So Josh’s nickname cannot be Curly and it cannot be Ace.
Spider Curly Ace Fudgy
Dawn
Mark
Josh x xTina
So we know that Tina’s nickname cannot be Curly or Fudgy.
Spider Curly Ace Fudgy
Dawn
Mark
Josh x xTina x x
The third clue tells us that The third clue tells us that Spider, Curly and Dawn play Spider, Curly and Dawn play in the football team.in the football team.
So that must mean that Dawn cannot be Spider or Curly.
Spider Curly Ace Fudgy
Dawn x xMark
Josh x xTina x x
Spider cannot be Josh’s nickname either!
What else do we therefore know?
If Josh’s nickname is Fudgy, no one else can have that nickname.
Let’s add that to the diagram.
Spider Curly Ace Fudgy
Dawn x x xMark xJosh x x x OTina x x
Spider Curly Ace Fudgy
Dawn x x O xMark x xJosh x x x OTina x x x
Spider Curly Ace Fudgy
Dawn x x O xMark x x xJosh x x x OTina O x x x
Spider Curly Ace Fudgy
Dawn x x O xMark x O x xJosh x x x OTina O x x x
At this point it’s always a good idea to look though the clues again to check you haven’t missed anything.
Have we?
No, so all the information we need must now be on our picture.
Can we learn anything else?
Spider Curly Ace Fudgy
Dawn x x O xMark x O x xJosh x x x OTina O x x x
Dawn ~ Ace Mark ~ Curly Josh ~ Fudgy Tina ~ Spider
Look back at the criteria and clues for the problem.
Does this solution fit with the information we were given?
Yes it does so we are correct!
Sarah, Jenny, Ranjit and Paul each choose a sandwich filling. They can choose from:~ tuna,~ egg salad,~ cheese, or~ chicken.
Each child chooses a different filling.Clues Sarah doesn’t like fish. Jenny cannot eat dairy products. Ranjit does not eat meat or fish. Jenny doesn’t like tuna or chicken. Which sandwich filling does each child
choose?
Tuna Egg Salad
Cheese Chicken
Sarah
Jenny
Ranjit
Paul
Tuna Egg Salad
Cheese Chicken
Sarah X
Jenny
Ranjit
Paul
Tuna Egg Salad
Cheese Chicken
Sarah X
Jenny X
Ranjit
Paul
Tuna Egg Salad
Cheese Chicken
Sarah X
Jenny X
Ranjit X X
Paul
Tuna Egg Salad
Cheese Chicken
Sarah X
Jenny X X X
Ranjit X X
Paul
Tuna Egg Salad
Cheese Chicken
Sarah X X
Jenny X O X X
Ranjit X X X
Paul X
Tuna Egg Salad
Cheese Chicken
Sarah X X X
Jenny X O X X
Ranjit X X O X
Paul X X
Tuna Egg Salad
Cheese Chicken
Sarah X X X O
Jenny X O X X
Ranjit X X O X
Paul X X X
Tuna Egg Salad
Cheese Chicken
Sarah X X X O
Jenny X O X X
Ranjit X X O X
Paul O X X X
Tuna Egg Salad
Cheese Chicken
Sarah X X X O
Jenny X O X X
Ranjit X X O X
Paul O X X X
Sarah – Chicken Jenny – Egg salad Ranjit – Cheese Paul - Tuna
1. Tom is neither the nurse nor the teacher.
2. Fred and the pilot play in a jazz band together.
3. The burger lover and the teacher are not musically inclined.
4. Tom brought hot dogs.
5. Bill sat next to the burger fan and across from the steak lover.
6. The secretary does not play an instrument or sing.
Tom, John, Fred, and Bill each brought his favorite meat to barbecue. From the clues
below, determine each man’s occupation and favorite meat.
Who’s Who at the barbecue?Who’s Who at the barbecue?
Tom – Pilot - HdogJohn – Scty - BurgFred – Nurse - SteakBill – Tchr - Chkn
• Mark traits from clues. • Combine clues.• Eliminate possibilities and act on eliminated
possibilities.• Substitute.• Cross-correlate.• For other approaches or problems: Study the
introduction, and test assumptions.
