David proposes a solution to calculate the weight of tomatoes after drying. Originally there were 100 pounds of tomatoes that were 99% water and 1% solids. As the tomatoes dry to 98% water, the solids remain 1 pound. An algebraic equation is set up where 2% of the total dried weight X equals the 1 pound of solids. Solving for X reveals the total dried weight is 50 pounds. Adding this to the original 148 pounds of Tommy and the box gives a final weight of 198 pounds.