You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: How many seconds will a train 100 meters long take to cross a bridge 250 meters long if the speed of the train is 36 kmph?

 Option A: 54 sec

 Option B: 35 sec

 Option C: 25 sec

 Option D: 45 sec

 Option E: 24 sec

A: Option B
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Q: Question: The time taken by a man to row his boat upstream is twice the time taken by him to row the same distance downstream. If the speed of the boat in still water is 42 kmph, find the speed of the stream?

 Option A: 12

 Option B: 15

 Option C: 14

 Option D: 18

 Option E: 19

A: Option C
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Q: Question: Rs. 6000 is lent out in two parts. One part is lent at 5% p.a simple interest and the other is lent at 10% p.a simple interest. The total interest at the end of one year was Rs. 450. Find the ratio of the amounts lent at the lower rate and higher rate of interest?

 Option A: 5:1

 Option B: 5:5

 Option C: 5:8

 Option D: 5:4

 Option E: 5:2

A:
Option B
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