[{"id": 1, "type": "multiple_choice", "skill": "fractions", "options": ["1/2", "3/4", "3/8", "2/4"], "question": "What is 1/4 + 2/4?", "difficulty": "medium", "explanation": "Same denominator: add numerators. (1+2)/4=3/4.", "needs_review": false, "correct_answer": "3/4"}, {"id": 2, "type": "short_answer", "skill": "fractions", "question": "Simplify: 6/8", "difficulty": "medium", "explanation": "Divide numerator and denominator by GCF (2): 6÷2/8÷2=3/4.", "needs_review": false, "correct_answer": "3/4"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 7", "difficulty": "medium", "explanation": "Multiply: 16×7=112", "needs_review": false, "correct_answer": "112"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 6", "difficulty": "medium", "explanation": "Multiply: 17×6=102", "needs_review": false, "correct_answer": "102"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 10", "difficulty": "medium", "explanation": "Multiply: 4×10=40", "needs_review": false, "correct_answer": "40"}]