Determine the two z-scores that divide the area under the standard normal curve into a middle 0.874 area and two outside 0.063 areas. a. -1.45, 1.45 b. -1.39, 1.39
c. -1.53, 1.53
d. -1.46, 1.46

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?

Read the equations in the table below. then drag a description of the situation and a table to represent each equation. indicate whether each of the relationships is proportional or non-proportional.

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.