Nisha wants to study for 5 hours for the spelling bee. If she studies 1/3 hour per night, how many nights will she have to study?

25 nights. 20 minutes is 1 third of an hour. 5 hours is 300 minutes. To get 300 from 20, you multiply 20 by 25. 25 is the number of nights she would have to study if she were to study 1/3 of an hour each night