If mary is shorter then casey and casey is taller than rick, sarah is taller than rick and sarah is shorter than casey whose the tallest?

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

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Tom had a total of $220 and he spent $35 on a basketball ticket . what percent of his money did he have left?