Hello please help..

The owner of a computer repair shop has determined that their daily revenue has mean​ $7200 and standard deviation​ $1200. The daily revenue totals for the next 30 days will be monitored. What is the probability that the mean daily revenue for the next 30 days will be between​ $7000 and​ $7500? Round to four decimal places

1 answer

You can play around with Z table stuff at
http://davidmlane.com/hyperstat/z_table.html