Two trains set off at the same time from each end of a single straight railway line which is 100km long. The first train travels at a constant speed of 55kmh. The second train travels at a constant speed of 70 kmh. A very fast bee, Sidney travels at 100 kmh. Sidney starts off in front of the first train and flies continuously back and forth between the two trains. How far does Sidney fly before he is squashed between the two trains? (Apologies to bee lovers everywhere!
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Solution on page 30.