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What is the answer to 32÷(-2)+ (-25)÷5

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2 Answers

PEMDAS first.  Makes sure you are following the rules of PEMDAS which states that division should be done before addition.
 
So let's look at each of the division in the problem.
 
32/-2 =
-25/5 = 
 
When you are dividing or multiplying by a negative number, there are rules. 
A -number times/divide a +number will result in a -answer. (-2*+2 = -4) or ( 4/ -2 = -2)
A -number times/divide a -number will result in a + answer. (-2* -2 = +4) or (-4/-2 = +2)
 
Therefor in our problem:
32/-2 = - 8
-25/5 = - 5
 
Since we are adding in the original problem, anytime your signs are the same, just combine the numbers. In this case, both numbers are negative, just use the negative sign and combine. 
 
-13 
Do you know 32÷2?  Rather than give you that answer, I'm going to call it Z.  =)
How about 25÷5?  I'm going to call the answer to that Y.
Because there's a negative on the 2, the answer will be negative.
Same for the 5.
So we actually have (-Z) + (-Y). 
Remember that for multiplying and dividing, one negative makes the whole thing negative, but two negatives cancel each other?  With adding and subtracting, it's different.  Think of it like a number line.  You have -Z and -Y more, so you're extra far into the negative area of the line.  So the final answer should be negative.
 
Simply reading explanations like this doesn't work as well for most people as hearing and seeing it written in front of you, so I hope this was helpful and not just 'noise.'  But it wouldn't help you really to just give you the answer like you seemed to ask.