8x − 7y = –5
–x + 4y = –15

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?

Sara can take no more than 22 pounds of luggage on a trip.her suitcase weighs 112 ounces.how many more pounds can she pack without going over the limit?

[tex]5 \times1 \frac{12}{13} [/tex] me