Jennifer is training for a marathon and wants to determine her average speed during her training sessions. On Monday, she ran for 1 hour and 15 minutes covering a distance of 10 kilometers. On Wednesday, she ran for 45 minutes covering 6 kilometers. On Friday, she ran for 1 hour covering 8 kilometers. What was her average speed in kilometers per hour for these three training sessions? Let's think step by step and output the final answer within \boxed{}.
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