If a given particle has two up quarks and one down quark, what charge will it have? -(2)/(3)e 0 +e +(2)/(3)e

The answer is +e, i got 100% on it for plato. I figured it out as if a quark is x so whats 2x-1x = x because x represents 1, so i guessed that e was for quarks and since it was positive it had a plus sign in front of it 

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.