Kim is making bookmarks with ribbon. each bookmark needs twelve inches of ribbon. kim has thirty six inches of ribbon. how many bookmarks can kim make?

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?

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

I’m still confused on how to work the percentages