Apples 32

A woman sold half of her apples to the 1st customer, half of the remainder to the 2nd customer, half of what remained to the 3rd customer, and again half of the remainder to the 4th customer. She was then left with 15 apples. What was the total number of apples she had originally?

Final Answer:

a =  240

Step-by-step explanation:

$$\begin{gathered} e=15 \\ d=2\cdot e=2\cdot 15=30 \\ c=2\cdot d=2\cdot 30=60 \\ b=2\cdot c=2\cdot 60=120 \\ a=2\cdot b=2\cdot 120=240 \\ a=2^4\cdot e \end{gathered}$$

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