Happy Island has 60 turtles. This means there are 10 more than 2 times as many turtles on Happy Island as on Lonely Island. How many turtles are there on Lonely Island?
After subtracting 10 from the number of turtles on Happy Island, we get 60 - 10 = <<60-10=50>>50 turtles
Dividing this number by two, we find that the number of turtles on Lonely Island is 50/2=<<50/2=25>>25 turtles.
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