ERROR PATTERN ANALYSIS The student added the numerators and denominators directly $1+1=2$ and $2+3=5$. Misconception: Fractions are treated as whole numbers. Missing step: Finding a common denominator. PROFICIENCY SCORING Mastery $M = \frac{0}{1} \times 100 = 0\%$. Difficulty of missing concept: $8/10$. REMEDIAL PATHWAY 1 Relearn the concept of equivalent fractions. 2 Practice finding the Least Common Multiple (LCM) of denominators. 3 Use visual pie charts to see why $1/2 + 1/3$ cannot be $2/5$. MASTERY CHECKPOINT 1 What is the LCM of $4$ and $6$? 2 Solve $1/4 + 1/6$ and explain your steps.