Population Differences

Today in class we talked about population in different countries. We mainly talked about why the average lifetime in some cultures is higher then others. In wealthier countries the average lifetime is high then say the countries that dint have much. But why is that? When you think about it, if you have more money your area or home seems to be more neat and nicer then say someone who's living in a trailer. Just because its a trailer doesn't mean its a bad home it  just means its not as sanitary. When things aren't as clean you seem to get sick easier and then you might not have the money to go to the doctors or pay for mediation. Then it makes the area a lot more unsanitary and leads to more deaths. But, the money differences in countries is huge and it's because of unemployment and population. Its shouldn't be this drastic because then it causes many issues for this world. They shouldn't be paying people a dollar 25 a day when they're working 15 hours a day and then be paying someone a billion of dollars or more just to wear the product. Jobs and employment are changing this world and they way people live. It should be changed!