A certain ore is 382 nickel by mass How many kilograms of th

A certain ore is 38.2% nickel by mass. How many kilograms of this ore would you need to dig up to have 40.0 g of nickel?

Solution

mass % of nickel = 38.2 %

38.2 g Nickel   --------------> 100 g of ore

40.0 g Nickel     ------------------>   ??

mass of ore needed = 40 x 100 / 38.2

                                 = 104.7 g

mass of ore need = 0.105 kg