The task is to generate the correct answer for a given math problem.

Q: 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 ?

A: 36 kmph
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Q: Problem: a train running at the speed of 72 km / hr crosses a pole in 9 seconds . find the length of the train .

A: 180 meter
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Q: Problem: in a new housing development , trees are to be planted along the sidewalk of a certain street . each tree takes up one square foot of sidewalk space , and there are to be 12 feet between each tree . how many trees can be planted if the road is 157 feet long ?

A:
1
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