**Rockwell Hardness Probability Analysis**The Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.5. (Round your answers to four decimal places.)### (a) Probability for a Sample of 14 PinsIf the distribution is normal, what is the probability that the sample mean hardness for a random sample of 14 pins is at least 51?- **Answer**: 0.6667 (This value appears with a cross next to it, indicating it's incorrect.)### (b) Probability for a Sample of 39 PinsWhat is the (approximate) probability that the sample mean hardness for a random sample of 39 pins is at least 51?- **Answer**: [Blank area for the answer input]**Note**: An orange button labeled "USE SALT" is present, likely indicating a tool or feature for calculations.

It is given that the mean is 50 and standard deviation is 1.5.

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.5. (Round your answers to four decimal places.) A USE SALT (a) If the distribution is normal, what is the probability that the sample mean hardness for a random sample of 14 pins is at least 51? 0.6667 (b) What is the (approximate) probability that the sample mean hardness for a random sample of 39 pins is at least 51?

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.5. (Round your answers to four decimal places.) A USE SALT (a) If the distribution is normal, what is the probability that the sample mean hardness for a random sample of 14 pins is at least 51? 0.6667 (b) What is the (approximate) probability that the sample mean hardness for a random sample of 39 pins is at least 51?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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