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MATH / When Trilisa takes pictures, they turn out with probability (1)/(5). She wants to take enough pictures so that the probability of at least one turning out is at least (3)/(4). How …

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problem

When Trilisa takes pictures, they turn out with probability 15\frac{1}{5}. She wants to take enough pictures so that the probability of at least one turning out is at least 34\frac{3}{4}. How few pictures can she take to accomplish this?
Plain-text mathematical notation (without MathML)
When Trilisa takes pictures, they turn out with probability (1)/(5). She wants to take enough pictures so that the probability of at least one turning out is at least (3)/(4). How few pictures can she take to accomplish this?
Original LaTeX notation
When Trilisa takes pictures, they turn out with probability $\frac{1}{5}$. She wants to take enough pictures so that the probability of at least one turning out is at least $\frac{3}{4}$. How few pictures can she take to accomplish this?

level

Level 5

type

Counting & Probability

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