We know that the tub is 5 pounds, and costs $10.25. We also know that n is in dollars per pound. Dollars per pound can be written as the product of dollars, divided by pounds, so we can plug that in being n = $10.25/5, next we want to make the equation contain an integer on both sides and not contain any fractions, so we multiply both sides by 5, resulting in 5n = $10.25
