Answer:
9
Step-by-step explanation:
Sammy's rate of eating pizza is ...
pizza/hour = (6/7)/(2/21) = (18/21)/(2/21) = 18/2 = 9
Sammy eats pizza at the rate of 9 pizzas in one hour.
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Comment on the question
Sammy may only eat 6/7 of a pizza in an hour, because he is no longer hungry after eating that much.
