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Creating Your Own FormulaeDescription: Creating your own formulas for word questions involving Integers.

Objective:

Now that you have practiced using formulas for word questions, you can create your own formulas to apply to unfamiliar numbers (Integers).

Help on this Topic:

Dealing with Integers can be a little unfamiliar and unintuitive. It can be hard for us to understand what we are being asked to do.
To help with this we first create a METHOD to solve the question using numbers that are more familiar to us, and then we apply the method to the numbers in the question.
 
Example 1:
The temperature in Ireland is -6 degrees. The temperature in France is -4 degrees more than Ireland.
Step 1: change the question to have numbers we can work with easily (small counting numbers) and find a method to solve it.
You can pick any number that works for you, in this question I'm going to use the numbers +6 and +4
New question : The temperature in Ireland is +6 degrees. The temperature in France is 4 degrees more than Ireland.
It's easier for me to see now that to find the temperature in France I need to add these two values together.
So my Method to find the temperature in France is: Add the two numbers.  6 + 4 = 10.
 
Step 2: Once I have a method (i.e. I know what to do - i.e. ADD the two numbers) I use this method with the values I was given in the actual question.
So, ADD the two values
(-6)  +  (−4)
= -10
 
 
Example 2.
The temperature in Ireland is -4 degrees. The temperature in France is -7 degrees less than Ireland.
Step 1: change the question using numbers that are easy for me to understand, and then find a method to solve it.
Change the numbers to whatever you like.  I picked 6, and 4 here.
New question : The temperature in Ireland is 6 degrees. The temperature in France is 4 degrees less than Ireland.
Now I think, "How would I figure out the temperature in France if it less than the temperature in Ireland?"
My answer is "I would take the temperature in Ireland (6 degrees) and SUBTRACT that 4 degrees.
So my method to find the temperature in France is
: Subtract the second number from the first. 
(6) - (4)
= 2 degrees.
 
Step 2: Do the same thing (Subtract), but use the numbers you were given in the question.
 Remember that subtracting a negative value is the same as adding.
 
(-4)  -  (-7)
(-4) + 7
= +3