A woman leaves a city on her bicycle at a constant
speed of 18 km/h. A friend of hers who has been
delayed leaves 30 minutes later and travels in the
same direction. The friend, intending to catch
up,
rides at a constant 30 km/h. Draw a picture
representing the situation. Then, calculate:

a. How long after the first cyclist set out does
the second one catch her? Express the time in
hours, minutes and seconds.

b. How far from the starting point will they be?
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