How many ways are there to answer a $10$-question true/false test, where at least $3$ of the questions have been answered with a false?
Question:
How many ways are there to answer a $10$-question true/false test, where at least $3$ of the questions have been answered with a false?
Answer:
Let's think step by step.

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How many ways are there to answer a $10$-question true/false test, where at least $3$ of the questions have been answered with a false?
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