Answer: Matt
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Step-by-step explanation:
5 cupcakes : 20 min
5/5 cupcakes : 20/5 min
1 cupcake : 4 min
Carolyn eats 1 cupcake every 4 minutes
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6 cupcakes : 22 min
6/6 cupcakes : 22/6 min
1 cupcake : 3.67 min
Matt eats 1 cupcake every 3.67 minutes (roughly).
Matt is the faster eater since his time value per cupcake is smaller.