Which is correct?
The iPhone cases that are retailing for $45 were manufactured for $1 ______.
a. a piece
These two are easy to confuse because the meanings are similar. They are distinct, though. Apiece means each. For example: The movie tickets cost $9.50 apiece.
As two words, a piece means per piece, for something that comes in discrete pieces. For example: “We sold cake for $5 a piece” means that we sold each piece of cake for $5. If we said we sold cake for $5 apiece, that would mean that we sold each cake for $5. So make sure you get the signs right at your bake sale if you want to make any money.
Paul Brians explains the difference between apiece and a piece in Common Errors in English Usage.
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