Data Sufficiency

Help me with the answer for this one

I think it should be D.

Whats the OA ?

B forms a quadratic equation, did you solve the equation before concluding on D?

The quadratic eqn I got is

f^2 + 6f - 2800 = 0

Solving this you get 2 values one positive and one negative.

Obviously the number of units cannot be negative. But the other solution is positive. Go with that. So it means Stmt 2 also gives a unique answer.

Each of these stmts independently are sufficient.

Hence Ans (D)

What is the OA?

OA is D

F is the total number of units
X is the unit price

given
FX=1750,000
(1) (F/2) X 250K= 1750K

BCE out answer between A,D

given
FX=1750,000
(2) (F+6) (X-3750)=1750K
Two different equations with two variables. we can solve for F & X

D is my answer

BTW, I did not solve the equation. Do you guys think GMAT will trick us into solution with two negative solutions?

netigen wrote:B forms a quadratic equation, did you solve the equation before concluding on D?

Hi Netigen,

I did not solve the equation. But to be sure that the roots were not imaginary.. I did find the Discriminant, D = b^2 - 4ac.

Since D was greater than 0 (obviously didn't calculate it, just saw it is +ve by signs) i thought I have a real solution.

I took a risk by not calcutaing the roots as there might be two values of X still. But then I thought the question would be asking too much too ask me to check both values of X, well, considering the complexity of the question.

I would do that in real GMAT as well if the equations were complex.

In this case , solving the equations is necessary because, if the equation did not have a negative root, then Stmt would give 2 different answers and if none matched with that of Stmt 1

The answer would either be (A) Stmt1 alone is sufficient.

Incase one of the roots of equation matched with that of Stmt1, answer would be C. since we need both Stmts to arrive at the final answer.

Thats why it is always better to be sure by solving the equation