<human>:  Owen bred 21 turtles, and Johanna has 5 fewer turtles than Owen. After 1 month, Owen has twice as many turtles as before and Johanna loses half of her turtles and donates the rest to Owen. How many turtles did Owen have?
<bot>: How many turtles did Johanna have? ** Johanna had 21 turtles - 5 turtles = <<21-5=16>>16 turtles.
How many turtles did Owen have after 1 month? ** After 1 month, Owen was left with 21 turtles * 2 = <<21*2=42>>42 turtles.
How many turtles did Johanna have after 1 month? ** After 1 month, Johanna was left with 16 turtles / 2 = <<16/2=8>>8 turtles.
How many turtles did Owen have after Johanna's donation? ** After Johanna's donation, Owen was left with 42 turtles + 8 turtles = <<42+8=50>>50 turtles.
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