Don't S1 and S2 run counter to each other?? How can the cost of A last year be $10 more than B (S2) but the price of model B last year be 10% more than A (S1)???

If the price of a mobile phone of model A increased by 15% from last year and the price of a mobile phone of model B decreased by 25% from last year, is the current price of a mobile phone of model A greater than that of a mobile phone of model B ?

1. Last year, the price of a mobile phone of model B was 10 percent greater than that of a mobile phone of model A
2. Last year, model A cost $10 more than model B


is it A?

OE never talks about condition no (2)

and OA given is D
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But you're picking a case that works.

What if A = 1
and B = 11

Then new A = 1.15
new B = 8.25

The OA is wrong.

The price of a mobile phone of model A increased by 15% from last year while the price of a mobile phone of model B decreased by 25% from last year. Is the current price of a mobile phone of model A bigger than that of a mobile phone of model B?

1. Last year the price of a mobile phone of model B was 10 percent bigger than that of a mobile phone of model A
2. Last year model A cost $10 more than model B

(C) 2008 GMAT Club - m09#23

* Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient
* Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient
* BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient
* EACH statement ALONE is sufficient
* Statements (1) and (2) TOGETHER are NOT sufficient


Here's an explanation,

Let Price Cell Phone A last year be X , and that of Model B be Y
According to Information given in the question

Model A's current price = X + 15/100X , Model B's current price = Y - 25/100Y

Now lets work with the statements given.

1) Last year the price of a mobile phone of model B was 10 percent bigger than that of a mobile phone of model A

Y = 10/100X , so we have a relationship between Y and X , Substitute this value of Y in Model B's current price

Model B's current price = 10/100X - (25/100*10/100)X, which is clearly lesser than Model A's current price X + 15/100X - hence sufficient.

2)Last year model A cost $10 more than model B

X = Y + 10 or Y = X - 10 , again substitute this value in Model B's current Price and we can compare the two to tell if X's current price is greater or less than B's current price.

No point getting bogged down in calculations.

Hence answer - D, each statement alone is sufficient.
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