The table below shows the amount of lemon juice and sugar needed to make three different-sized batches of lemonade using the same recipe. Lemon juice (\text{mL}mLstart text, m, L, end text) Sugar (\text{g}gstart text, g, end text)
Batch A 500500500 200200200
Batch B 750750750 300300300
Batch C 150015001500 600600600
Write an equation to describe the relationship between jjj, the amount of lemon juice in \text{mL}start text, m, L, end text, and sss, the amount of sugar in \text{g}gstart text, g, end text.