I. The final angle deduction problems in the 6th Grade Everyday Math curriculum (Student Math Journal I, p. 201) [click to enlarge]:
II. The first angle deduction problems in the 6th Grade Singapore Math Primary curriculum (Primary Mathematics Workbook 6B, p. 85) [click to enlarge]:
III. Extra Credit
Which problem set better prepares students for formal proofs in geometry?
Given that U.S. Reform Math geometry programs have drastically reduced or eliminated formal proofs, does this matter?