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

Q: Problem: bob wants to run a mile in the same time as his sister . if bob ’ s time for a mile is currently 11 minutes 20 seconds and his sister ’ s time is currently 9 minutes 36 seconds , by what percent does bob need to improve his time in order run a mile in the same time as his sister ?

A: 15 
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Q: Problem: a number x is mistakenly divided by 10 instead of being multiplied by 10 . what is the percentage error in the result ?

A: - 99 %
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Q: Problem: a man performs 3 / 5 of the total journey by rail , 17 / 20 by bus and the remaining 6.5 km on foot . his total journey is

A:
130 km
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