Quinn's library was hosting a summer reading challenge.  For every 5 books you read, you a coupon for a free donut at a nearby bakery.  Quinn decided he could read 2 books a week for 10 weeks total.  How many free donuts would Quinn be eligible for?
Quinn will read 2 books per week for 10 weeks so 2*10=<<2*10=20>>20 books
If he reads 5 books, he gets a free donut. So if he reads 20/5 = 4 free donuts
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