If the average weight of the chickens on Farm One is 12 pounds, how many chickens are there on Farm Two?

(1) The average weight of the chickens on Farm Two is 13 pounds.

(2) The total weight of the chickens on Farm Two is 6 pounds less than the total weight of the chickens on Farm One.
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You were close, But made mistake here.

The statement 2 says that the TOTAL weight of Chicken in farm 2 is 6 less than the TOTAL weight of Chicken in farm 1. So the above method you used is wrong. As 12 and 13 are the AVERAGE weight of the chickens in the respective farms, not total weight.

Official Explanation :

We need to find the number of chicken in farm 2(N2)

(1) Average weight is 13. So as per the average formula we know that

\(13 = \frac{Total (T2)}{N2}\)

No enough info, so in sufficient.

(2) As per the statement T2= T1-6

Since we dont know the total weight of chicken in farm 1- Insufficient.

Combining (1) & (2),

\(Average = \frac{T2}{N2}\)

We know T2= T1-6, when we substitute.

\(13= \frac{(T1-6)}{N2}\)

Since we still don't know the total weight(T1) of the chickens in the farm 1. So both statement together are not sufficient.

Answer is E.
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Oh ok. My mistake

In DS we just need to find whether the two given statement are sufficient to find the answer. We don't have to plug in. If at all we do that, we may have different values for X and Y.

In this problem, we still don't know the total value of chicken in farm 1. Hence we are not able to find the number of chicken in farm 2. So E.
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There are other solutions. For example, x=20 and y=18.
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