MCAS Open-Response Questions & Answers. Mathematics – Middle School Level. Wachusett Regional School District. 1. Rev. April 2003 srm. Question #1 ..... If the grocer uses the same number of 5kg bags as. 2kg bags, how many bags did he use in all? Answer #16 x = total number of bags. 5(1/2x) + 2(1/2 x) = 252.