Please help-What are the lengths of EF and FG to the nearest tenth

If 1 is divided by the sum of y& 4.the result is equal to 3 divided by 4, find the value of m

What is the size of the matrix resulting from

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?