math question, please help!! thanks?

Antonio Ruiz pays a monthly premium of $175 for health insurance. He can purchase dental care and vision care insurance for his family at an additional cost. The dental premium is $595 and the vision premium is $195 per year. What is his total monthly premium for all his insurance?
--------------------
Ok, this is a great sample question for watching one important example. Units are very important. We have $/yr and need $/m, right? We divide by 12 to get that. (technically, we multiply by 1yr/12m but it is the same thing and a useful shortcut) So, dental is 595/12 per month and vision is 195/12 per month and normal is 175 per month. So, (595+195)/12 + 175 = 240.83 <== The answer!
Source