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e) What perce d) If 25 women are randomlyses count is I the normal range. If z i

ID: 3356652 • Letter: E

Question

e) What perce d) If 25 women are randomlyses count is I the normal range. If z is a standard normal variable, find the probability 7) The probability that z lies between -1.22 and 1.47 The graph depicts the standard normal distribution with mean 0 and standard deviation 1. 8) Shaded area is 0.6215. Find the indicate z-score. Assume that X has a normal distribution, and find the indicated probability 9) The mean is = 97.0 and the standard deviation is = 1.2. Find the probability that X is less than 1000. The mean is = 1.52 and the standard deviation is Find the probability that X is greater than 0.9. 10) 0.61.

Explanation / Answer

Q7) P(-1.22<z<1.47)

Use Excel function

NORMSDIST(1.47)-NORMSDIST(-1.22)

= 0.8180

B) Use Excel function

NORMSDIST(1-0.6215)

= -0.3094

q9) P(x<100)

= P(z<(100-97)/1.2)

= 0.9938

q10) P(x>0.9)

= P(z>(0.9-1.52)/0.61)

= 0.8453