First, since we know that the total number of stamps that Josef has is j and that Mai will have j – 500 stamps, we can set up an equation. The total number of stamps should be j + (j – 500), which can be simplified to 2j – 500. We can set up cross multiplication since we know Josef has 60% of the stamps. = When we cross multiply, we get 100j = 60(2j – 500). Next, using the distributive property, multiply to get 100j = 60(2j – 500). Then use the additive inverse property to subtract 120j from both sides and get -20j = -30,000. Finally, divide by -20 to get j = 1,500.
