How much does 100g grams of platinum cost

Today (April 28), platinum closed at $1,012 per troy ounce,

and gold closed at $1,243 the ounce.

1 troy ounce = 31.1 grams.

So 100g of platinum would be worth (100/31.1) x $1,012 = $3,254

and 100g of gold would be worth (100/31.1) x $1,243 = $$3,997 (rounded).