dhushan wrote:
Looking over the answer to the solution, I am confused as to why their needs to be a minimum and maximum of 4 to 6 piglets respectively. Given that their is 3/4 of the Oats and 5/6 of the Barley, why could their not be 7 piglet where each received 3/28 of the Oats and 5/42 of the Barley? Or following the same logic, even more than 7 piglets?
You're not using one crucial piece of information  each pig ate the same total amount of food. We know that one pig had 1/4 of the oats and 1/6 of the barley. If each other pig had 3/28 of the oats, then each other pig had less oats than the first pig, and if each other pig had 5/42 of the barley, then each other pig had less barley than the first pig. If the other pigs had less oats and less barley than the first pig, there's no way they could have had the same total amount of food.
chetan2u wrote:
restricting the no between 4 and 6 because some piglet has 1/4 of oats and 1/6 of something else does not make senseand cannot be correct
can someone post OA..
from 2 statements one can get 3o+2b=6..(i)
and if t is total no of piglets total food=t*1/2=t/2 pounds..
also total food=b+o=t/2....(ii)
two eq but three variables o,b and t so ans should be E
You aren't using one crucial piece of information: t must be an integer (and o and b must be positive). When you have restrictions on your unknowns, then counting equations and unknowns can be very misleading (see Q123 in the DS section of OG12 for another example). If the solution I posted above doesn't make sense to you, you can proceed algebraically, using the equations you wrote above. First, multiply the equation b + o = t/2 by 2 on both sides, and subtract from the equation 3o + 2b = 6:
3o+2b = 6

2o + 2b = to = 6  t
Now, o is clearly positive, so the right side of the equation above must be positive, and t < 6.
Next, multiply the equation b + o = t/2 by 3 on both sides, and subtract the equation 3o + 2b = 6 from it:
3o + 3b = 3t/2

3o + 2b = 6 b = 1.5t  6
2b/3 = t  4
Now b is clearly positive, so the right side of the above equation must be positive, and t > 4.
Since 4 < t < 6, and t is an integer, t = 5. The answer is C.
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