Zena can get an item online for $19 that
weighs 8 pounds. Shipping and handling
costs $0.49 per pound. She can also buy the
same item locally for $26.95, and she has
a $5 off coupon. Which is the better buy?

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?

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.

How many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.) how many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.)