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3 years ago

What expression is equivalent to 2.2-2.5?

Mathematics

2 answers:

Pani-rosa [81]3 years ago

4 0

Hi Camrynb10705oxknsv!
So let's take a look at the answers they give. A is 2.5 - 2.2 and all that is is switching the numbers so that isn't right. B they do addition instead of subtraction so that can't be right. C they do 2.2 + (-2.5) and when you add a negative number it's like subtraction because a negative number is under 0 and so your adding a number under 0 so you go down. So the answer is C.
If you need me to explain it different let me know. Hope this helps!

dybincka [34]3 years ago

4 0

The answer is C. How we know:
The origional expression would equate to -0.3
The reason A is incorrect is that you can not change the order of subtraction. This answer equates to 0.3.
The reason B is incorrect is that adding is not the same as subtracting. This answer equates to 4.7.
The reason D is incorrect is that subtracting a negative is the same as adding. This would equate to 4.7
The reason C is correct is that adding negative is the same as subtracting. This would equate to -0.3.

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