A set of average city temperatures in July are normally distributed with a mean of 23.5 degrees Celsius and a standard deviation of 2 degrees Celsius. The average temperature of the City of Van Nuys is 23 degrees Celsius.

One cell phone plan charges $20 per month plus $0.15 per minute used. a second cell phone plan charges $35 per month plus $0.10 per minute used. write and solve an equation to find the number of minutes you must talk to have the same cost for both calling plans.