If the absolute value of a number is added to the original number will the sum always equal 0

Arestaurant needs to buy thirty-seven new plates. if each box has five plates in it, how many boxes will they need to buy?

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You just purchased two coins at a price of $670 each. because one of the coins is more collectible, you believe that its value will increase at a rate of 7.1 percent per year, while you believe the second coin will only increase at 6.5 percent per year. if you are correct, how much more will the first coin be worth in 15 years?