Mathematics Florida Standards (MAFS) Grade 4

MAFS. 4.OA.1.a Determine whether an equation is true or false by using comparative relational thinking. For example, without adding 60 and 24, determine whether the equation 60 + 24 = 57 + 27 is true or false. MAFS.4.OA.1.b Determine the unknown whole number in an equation relating four whole numbers using comparative relational thinking.

http://www.fldoe.org/core/fileparse.php/12087/urlt/G4_Mathematics_Florida_Standards.pdf