1. A Closer Look at Inductive vs. Deductive Reasoning

2. Deductive vs. Inductive Reasoning
The difference:
inductive reasoning uses patterns to arrive at a conclusion (conjecture)
deductive reasoning uses facts, rules, definitions or properties to arrive at a conclusion.

3. Inductive reasoning - Think of it like a
We start with specifics and move to generalities
Deductive reasoning – think of it like a
We start with generalities and move to specifics.

4. Examples of Inductive Reasoning
Some examples
Every quiz has been easy. Therefore, the test will be easy.
The teacher used PowerPoint in the last few classes. Therefore, the teacher will use PowerPoint tomorrow.
Every fall there have been hurricanes in the tropics. Therefore, there will be hurricanes in the tropics this coming fall.

5. Deductive Reasoning
An Example:
The catalog states that all entering freshmen must take a mathematics placement test.
You are an entering freshman.
Conclusion: You will have to take a mathematics placement test.

6. Inductive or Deductive Reasoning?
Geometry example…
60◦ x
What is the measure of angle x?
Triangle sum property - the sum of the angles of any triangle is always 180 degrees. Therefore, angle x = 30°

7. Inductive or Deductive Reasoning?
Geometry example…
What is the next shape in the sequence?