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put this solution on YOUR website!climbing for 3 hrs (8am-5am) at a rate of 240m/h, the climber covers 720m (240m * 3)to reach the 6500m level
the base camp is 720m below the 6500m level, or 5780m
the summit is 1620m (7400-5780) above the base camp
it takes 1620/240 or 6.75 hr to make the climb
arrival time is 5+6.75 or 11:45am