Souvenir hats, t-shirts, and jackets are sold at a rock concert. three hats, two t-shirts, and one jacket cost $140. two hats, two t-shirts, and two jackets cost $170. one hat, three t-shirts, and two jackets cost $180. find the prices of the individual items.

Find the solution of each of the following.

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible