<human>:  Hanna has twice as many erasers as Rachel. Rachel has three less than one-half as many erasers as Tanya has red erasers. If Tanya has 20 erasers, and half of them are red, how many erasers does Hanna have?
<bot>: How many red erasers does Tanya have? ** Half of Tanya's 20 erasers are red, so she has 20/2=<<20/2=10>>10 red erasers.
How many red erasers does Tanya have? ** One-half as many erasers as Tanya has red erasers is 10/2=<<10/2=5>>5 red erasers.
How many erasers does Rachel have? ** Rachel's three less than one-half as many erasers as Tanya's red erasers, which is 5-3=2 erasers.
How many erasers does Hanna have? ** Hanna has twice as many erasers as Rachel, for a total of 2*2=<<2*2=4>>4 erasers.
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