Backpack Weights

Edited from an AP Statistics - scatterplots activity by Bob Lochel with language now appropriate for IB Math AI with additional screens from Jennifer Brown's linear modelling activity. Original activities here: https://teacher.desmos.com/activitybuilder/custom/5a04839b7eaebf0ea419557f https://teacher.desmos.com/activitybuilder/custom/5f225ba23edde70407eff79c

By Becky Hall