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Zara has two fair coins in a closed box. She shakes the… | StemPy Lab
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Zara has two fair coins in a closed box. She shakes the box, and her brother sees through a small window that the first coin lies tails up. What is the chance that both coins lie tails up?
Mathematics
Easy
High School (11–12)
Statistics and Probability › Conditional Probability and Bayes' Theorem
AP
A-Level
IB
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StemPy Lab
Zara has two fair coins in a closed box. She shakes the box, and her brother sees through a small window that the first coin lies tails up. What is the chance that both coins lie tails up?
1
4
\dfrac{1}{4}
4
1
1
3
\dfrac{1}{3}
3
1
3
4
\dfrac{3}{4}
4
3
1
2
\dfrac{1}{2}
2
1
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