Answer
Peter can possibly buy 4 t-shirts.
Explanation:
$60 - 33 = 27 ( When he buys his pair of sneakers)
27 - 6 = 21 ( 1 pair of t-shirt )
21 - 6 = 15 ( 2 pair of t-shirt )
15 - 6 = 9 ( 3 pair of t-shirt )
9 - 6 = 3 ( 4 pair of t-shirt )
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