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Which is an equation for the nth terms of the sequence 12,15,18,21

What is 96 divided by 7,488mark as brainliest

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?