Answer: Choice A) $0.20
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Step-by-step explanation:
The store bought the batch for $100, and sold that same batch for $150. The profit of the entire batch is 150-100 = 50 dollars.
Divide this over 250 to get 50/250 = 0.20 dollars.
Their profit is $0.20 per pastry (ie 20 cents per pastry).
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You can think of it like this
50 dollar profit = 250 pastries
50/250 dollar profit = 250/250 pastries (dividing both sides by 250)
0.20 dollar profit = 1 pastry
That last equation tells us one pastry yields a profit of $0.20 or 20 cents.