Joey Chestnut ate 75 hotdogs to claim the record and Lisa has eaten 20 hot dogs so far, so she still needs to eat 75-20=<<75-20=55>>55 hotdogs to tie Joey Chestnut.
Lisa has a 10 minute time period to eat the hotdogs and half the time has already passed, which means Lisa has 10/2=<<10/2=5>>5 minutes left until the competition is over.
If she needs to eat 55 hotdogs to tie Joey Chestnut and there are 5 minutes left in the competition period then she needs to eat 55/5=<<55/5=11>>11 hot dogs per minute to have a chance of tying for a win.
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