maybeam wrote:

Which of Company X and Company Y earned the greater gross profit last year?

(1) Last year the expenses of Company X were 5/6 of the expenses of Company Y.

(2) Last year the revenues of Company X were $6 million less than the revenues of Company Y.

**Quote:**

what i did.

statement I & II independently insufficient.

Taking together,

let Y expenses be 6m

X expenses= 5m

Let Y revenue= 12m

X revenue= 12-6=6m

y profit= exp*R= 6*12=72m

x profit= 5*6= 30 m

therefore, Y profit> X profit.

Both statement together suff.

Now my Q is why is it wrong?

Two reasons why your solution is wrong:

1.

{Profit} = {Revenue} - {Expenses}, not {Profit} = {Revenue}*{Expenses}, as you've written.

2. One example is not enough to conclude that a statement is not sufficient.

Which of Company X and Company Y earned the greater gross profit last year?Since

{Profit} = {Revenue} - {Expenses}, then we are asked whether

R_x-E_x>R_y-E_y?

(1) Last year the expenses of Company X were 5/6 of the expenses of Company Y -->

E_x=\frac{5}{6}*E_y. Not sufficient, as we know nothing about the revenues.

(2) Last year the revenues of Company X were $6 million less than the revenues of Company Y -->

R_x=R_y-6,000,000. Not sufficient, as we know nothing about the expenses.

(1)+(2) So, according to the above the question becomes whether

(R_y-6,000,000)-\frac{5}{6}*E_y>R_y-E_y or whether

E_y>6*6,000,000. We don't know that, hence even taken together the statements are not sufficient.

Answer: E.

Hope it's clear.

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