The task is to generate the correct answer for a given math problem.
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Question: Problem: how many numbers between 200 and 600 are divisible by 4 , 5 and 6 ?

Answer: 6

Question: Problem: a cat chases a rat 6 hours after the rat runs . cat takes 4 hours to reach the rat . if the average speed of the cat is 90 kmph , what s the average speed of the rat ?

Answer: 36 kmph

Question: Problem: an investor can sell her microtron stock for 36 $ per share and her dynaco stock for 60 $ per share , if she sells 300 shares altogether , some of each stock , at an average price per share of 40 $ , how many shares of dynaco stock has she sold ?

Answer:
50