Best Answer:
5+5+5=15 (in money terms you get five dollars then another then another, now you have 15 dollars)

15-5=10 (someone takes away 5 dollars, now you have ten dollars)

10+5+5=20 (but they give you back ten dollars, now you have twenty dollars)

20-5=15 (now they take away five dollars, now you have fifteen dollars)

15+5=20 (but they give you five dollars back, now you have twenty dollars)

20X0=0 (think of the twenty dollars as how much money you have and you want to increase itif you multiplied your total of twenty dollars by two you would have two sets of twenty dollars, which equals forty dollars. if you multiply your twenty dollars by zero you would have zero sets of twenty dollars, hence 20X0=0)

Now for your question. The answer should be 15 because of the order of operations, which goes like this

1)Parenthesis

2)Exponents

3)Multiplication

4)Division

5)Additon

6)Subtraction

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