Find the sentiments of ab and bd. then check your answers using a different method.

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?

Just tell me how to set up the equation.

If i have 20$ and i gave 5$ away how much i got