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In each case, determine the value of the constant c that makes the probability statement correct. (Round your answers to two decimal places.)

(a) ?(c) = 0.9821


(b) P(0 ? Z ? c) = 0.2939


(c) P(c ? Z) = 0.1335


(d) P(?c ? Z ? c) = 0.6476


(e) P(c ? |Z|) = 0.0128

User Sush
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1 Answer

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Final answer:

To determine the value of the constant c in different probability statements involving a standard normal distribution, we use the properties of the distribution and find the corresponding z-scores. For each case, we use a standard normal distribution table or calculator to find the z-score that matches the given probability. Then, we determine the value of c based on the z-score.

Step-by-step explanation:

(a) ?(c) = 0.9821:

To determine the value of c, we need to find the z-score that corresponds to a probability of 0.9821 in a standard normal distribution. Using a standard normal distribution table or calculator, we find that the z-score is approximately 2.20. Therefore, c = 2.20.

(b) P(0 ≤ Z ≤ c) = 0.2939:

To find the value of c, we need to find the z-score that corresponds to a probability of 0.2939 when z is between 0 and c. Using a standard normal distribution table or calculator, we find that the z-score is approximately 0.58. Therefore, c = 0.58.

(c) P(c ≤ Z) = 0.1335:

To find the value of c, we need to find the z-score that corresponds to a probability of 0.1335 when z is greater than or equal to c. Using a standard normal distribution table or calculator, we find that the z-score is approximately -1.10. Therefore, c = -1.10.

(d) P(-c ≤ Z ≤ c) = 0.6476:

To find the value of c, we need to find the z-score that corresponds to a probability of 0.6476 when z is between -c and c. Using a standard normal distribution table or calculator, we find that the z-score is approximately 0.4. Therefore, c = 0.4.

(e) P(c ≤ |Z|) = 0.0128:

To find the value of c, we need to find the z-score that corresponds to a probability of 0.0128 when |z| is greater than or equal to c. Using a standard normal distribution table or calculator, we find that the z-score is approximately 2.71. Therefore, c = 2.71.

User Abtin Forouzandeh
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