What is
1/9 + 2/9? I need help

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?

Solve for n? [tex]z = \frac{3}{4} mn[/tex]

Graph the equationy= x+3[tex]y = x + 3[/tex]