Question 28 A scientist obtaired a normally distributed population of scores with a mean of 70...

Question

Question

math Statistics-And-Probability

Answer 1

Answer #1

Solution :

Given that ,

P(60 < x < 80) = P[(60 - 70)/ 10) < (x - $\mu$ ) / $\sigma$ < (80 - 70) / 10) ]

= P(-1 < z < 1)

= P(z < 1) - P(z < -1)

= 0.8413 - 0.1587

= 0.68

Proportion = 0.68

Answer 2

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