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Grade 7. Mathematics: Integers.
Can anyone help me answer this questions? I want the correct answers. No guessing or I think.

Evaluate each expression.
a.)  ( -6 )
=   
 
b.) - 4 + (-8)
=   
 
c.) 3 + 4 + (-5)

Evaluate each expression.
HINT: When we do subtraction change it to an addition of the opposite! KEEP, CHANGE, CHANGE.

a.) -3 - 10
=  
 b.) 8 - (-12)

 c.) 5 – 9

The melting point of mercury is -36 degrees F and its boiling point 672 degrees F. 
What is the difference between the boiling point and the melting point?
The expression I would use to solve this is: ?

The difference is : ? degrees F ?


A man enters an elevator at the first floor of a building.
He takes the elevator up 10 floors, down 3, up 11, and then down 20 to the basement.
How many floors below the first floor is the basement?

Hint: Think about when he goes UP floors, are those numbers positive or negative? And when he goes DOWN floors, are those numbers positive or negative?

Expression:

10 + ? + ? + (-20) = ?

So now I solve the mathematical expression by combining those values.
The answer to my expression is :

My solution is that the basement is how many floors below the first floor ?



The balance in your bank account is currently $350.00. 

Hint: Paying a bill is subtracting from the balance. Deposit is adding to a balance.

You pay a credit card bill for $250.00.  Now what is your bank account balance is ? $ 

You get a check from Grandma for $30.00 for your birthday that you deposit into your account. Now what is your account balance is ? $


Next you pay a bill for $120.00 and also pay a second bill for $50.00. 
Now what is your final and current balance is ? $