Least squares criterion - minimising the sum of squared residuals — IITM BS previous year questions

Least squares criterion - minimising the sum of squared residuals is part of Straight-Line Fit, Week 2 in Mathematics 1. Prasnya files every IIT Madras BS previous year question from this subtopic here, each one with a worked explanation. Take the whole set as a timed mock and you get accuracy, pacing and per-question analysis back.