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30 votes
30 votes
A toothpaste advertises that 30% of stains are removed after 1 week. As Alexa is brushing her teeth, she thinks "after 2 weeks, 60% of stains will be gone, and 90% after three weeks".

Using this reasoning, what percent of stains will be gone after four weeks? Does this result make sense? Why or why not?

User Canen
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1 Answer

14 votes
14 votes

Answer:

120%. doesn't make sense because there's nothing above 100%

User Manuel Escrig
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