(Hello, I have been having problems with this one. That 3 am studying can really hit you lol.)
 Two companies build houses.
 Company M builds half as many brick houses as wood houses.
 The table below shows the relationship between the number of brick houses and wood houses that Company N builds.
 Wood Houses: 5, 10, 15, 20
 Brick Houses: 3, 6, 9, 12
 Each company built 100 wood houses. How many more brick houses did Company N build than Company M?