Two runners

Two runners ran simultaneously towards each other from locations distant 21 km. The average speed of the first runner was 1/7 higher than the average speed of the second runner.

How long should each ran a 21 km, if you know that they meet after 77 minutes?

Result

t1 =  144.4 min
t2 =  165 min

Solution:

Solution in text t__2 =







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