A data set has a mean of 42 and a standard deviation of 7.8 if an element in the set is 54 find its z-score

One number is 4 less than 3 times a second number. if 3 more than two times the first number is decreased by 2 times the second number, the result is 11. use the substitution method. what is the first number?

Julie was able to walk 16 km through the zoo in 6 hours. how long will it take her to walk 24 km through the zoo?

Aweekly newspaper charges $72 for each inch in length and one column width. what is the cost of an ad that runs 2 column inches long and 2 columns wide? its not 288