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This Friday, Eva has a French vocabulary test as well as a Spanish vocabulary test. To prepare, she made a study card for each word, 40%40\% of which are French. Every time she picks a card, she sticks it back in the deck and shuffles again.\newlineIf Eva picks a study card from the deck 44 times during her first study session, what is the probability that exactly 44 cards have a French word?\newlineWrite your answer as a decimal rounded to the nearest thousandth.\newline____\newline

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Q. This Friday, Eva has a French vocabulary test as well as a Spanish vocabulary test. To prepare, she made a study card for each word, 40%40\% of which are French. Every time she picks a card, she sticks it back in the deck and shuffles again.\newlineIf Eva picks a study card from the deck 44 times during her first study session, what is the probability that exactly 44 cards have a French word?\newlineWrite your answer as a decimal rounded to the nearest thousandth.\newline____\newline
  1. Identify values: Identify the values of nn, kk, and pp for the binomial probability formula.\newlinen=4n = 4 (number of trials)\newlinek=4k = 4 (number of successful French word picks)\newlinep=0.40p = 0.40 (probability of picking a French card)
  2. Use binomial formula: Use the binomial probability formula P(X=k)=C(n,k)(p)k(1p)(nk)P(X = k) = C(n, k) \cdot (p)^k \cdot (1-p)^{(n-k)}. Substitute n=4n = 4, k=4k = 4, and p=0.40p = 0.40 into the formula. P(X=4)=C(4,4)(0.40)4(10.40)(44)P(X = 4) = C(4, 4) \cdot (0.40)^4 \cdot (1 - 0.40)^{(4 - 4)}
  3. Calculate C(4,4)C(4, 4): Calculate the value of C(4,4)C(4, 4).C(4,4)=4!4!(44)!=1C(4, 4) = \frac{4!}{4!(4 - 4)!} = 1
  4. Solve (0.40)4(0.40)^4: Solve (0.40)4(0.40)^4.(0.40)4=0.40×0.40×0.40×0.40=0.0256(0.40)^4 = 0.40 \times 0.40 \times 0.40 \times 0.40 = 0.0256
  5. Simplify (10.40)(44)(1 - 0.40)^{(4 - 4)}: Simplify (10.40)(44)(1 - 0.40)^{(4 - 4)}.(10.40)(44)=(0.60)0=1(1 - 0.40)^{(4 - 4)} = (0.60)^0 = 1
  6. Multiply values to find probability: Multiply all the values together to find the probability.\newlineP(X=4)=1×0.0256×1=0.0256P(X = 4) = 1 \times 0.0256 \times 1 = 0.0256\newlineRound the answer to the nearest thousandth.\newlineP(X=4)=0.026P(X = 4) = 0.026

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