Question

570 people are on a cruise ship. 1/3 of them are American, 1/6 of them are Australians, the rest are Europeans. How many Europeans are on the cruise ship

Answer 1

`\stackrel{ Americans }{570\left( \cfrac{1}{3} \right)}~~ + ~~\stackrel{ Australians }{570\left( \cfrac{1}{6} \right)}~~ + ~~\stackrel{ Europeans }{x}~~ = ~~570 \\\\\\ 190~~ + ~~95~~ + ~~x~~ = ~~570\implies 285+x=570\implies \boxed{x=285}`