The length and width of a rectangle whose length is 9 centimeters more than its width

Me find the measure to side a and the process to solve the problem you appreciate it : )

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?

Convert 2000 swiss francs to dutch guilders