MyRedemption wrote:
combine both : 12x-13y=6.
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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