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One line solution:
How long does it take for Wendy to catch up to Wilfred = = = 5 hours.
Explanation:
Wilfred is 2*20 = 40 km ahead (head start). It is the initial distance. And it is the NUMERATOR of my formula.
Their relative speed is 28-20 = 8 km/h meaning that the distance between them decreases at the rate of 8 km/h.
And it is the DENOMINATOR of my formula.
It gives the time to catch up = 5 hours.
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- Travel and Distance problems for two bodies moving in the same direction (catching up)
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