Molly and tess like to shop at the mall. their sister jessica prefers to play bocce ball instead. molly has $280 in her bank account and spends $40 on every trip to the mall. tess has $170 in her account and spends half as much as molly during each trip. jessica has $50 in her account and does not spend any of it. write and equation for each girl showing the relationship between money and the trips to the mal