I believe the question is a bit ambiguous.
First of all we are talking about ONLY year 2008 NOT all the curve and its changing over time
However, the stem says
If half of the customers who switched to Company Ausually, this means that we had a number X and the new number is Y so the difference is the number of customers who went from B to A
But the question accounts for ONLy the end value , which is 4
The pie chart shows the breakdown of profit from the various plans offered and indicates that 25 percent of the profit came from Plan X.
Plan X accounts for 25 percent of $220 million 5 $55 million. Half of $55 million is $27.5 million.
Divide $27.5 by 2 : $27.5 / 2 = $13.75. The correct choice is (B)
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