The task is to generate the correct answer for a given math problem.
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Question: Problem: what ratio must a shopkeeper mix peas and soybean of rs . 16 and rs . 25 / kg , as to obtain a mixture of rs . 21.50 ?

Answer: 7 : 11


Question: Problem: a farmer with 1,350 acres of land had planted his fields with corn , sugar cane , and tobacco in the ratio of 5 : 2 : 2 , respectively , but he wanted to make more money , so he shifted the ratio to 2 : 3 : 4 , respectively . how many more acres of land were planted with tobacco under the new system ?

Answer: 300


Question: Problem: if a ã — b = 2 a - 3 b + ab , then 3 ã — 2 + 2 ã — 3 is equal to :

Answer:
7