If a farmer sells 10 of his chickens, his stock of feed will last for 4 more days than planned, but if he buys 15 more chickens, he will run out of feed 3 days earlier than planned. If no chickens are sold or bought, the farmer will be exactly on schedule. How many chickens does the farmer have?  Choose the correct choice from the following answers:	A) 12	B) 24	C) 48	D) 35	E) 60
Say farmer has n chicken and he is good for d days.:-   We have 3 equations given in question:-   (n-10) * d+4 =(n+15) *(d-3) = n * d   Solving these: (You can solve 1st and 3rd and 2nd and 3rd together)   We get:   15d-3n=45   4n-10d =40   =&gt; n=35   Ans 35 it is!
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If a farmer sells 10 of his chickens, his stock of feed will last for 4 more days than planned, but if he buys 15 more chickens, he will run out of feed 3 days earlier than planned. If no chickens are sold or bought, the farmer will be exactly on schedule. How many chickens does the farmer have?