The tourist should have passed 30 km. Early in the morning he went 2 h with a speed 5km/h then 2 h with a speed of 4 km/h and he passed other way for too time. What its speed on the last site of a way? HELP PLEASE I GIVE 30 POINTS!

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1) 5*2=10km passed early in the morning 2) 2*4=8km passed in sluduyushchy 2 hours 3) 10+8=18km passed in 4 hours 4) 30-18=12 km other way 5) 12:2=6 km/h speed on other way 1) 2х5=10 km - there passed a tourist in the morning 2) 2х4=8 km - there passed a tourist after 3)30-(10+8)=12 km - other way 4) 12:2=6 km/h - the tourist's speed on the last site of a way
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