? I don’t get this and I need help please

Mat bought a phone for $100. he has to pay $30 per mouth. if he has paid $640 in total, how many mouth has he had the phone?

Suppose that in 2008 , 840,800 citizens died of a certain disease assuming the population of teh country is 399 miliion, what is the mortality rate in units of deaths per 100,000 people?

The median for the given set of six ordered data values is 29.5 9 12 25 __ 41 48 what is the missing value?