MP Board · Class 10 · Mathematics · Arithmetic ProgressionsIf the common difference of an AP is -4, and the 7th term ($a7$) is 4, what is the first term?
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Total Attempts: 7
Accuracy Rate: 42.9%
Step-by-Step Solution
Given $d = -4$ and $a_7 = 4$. Using $a_n = a + (n - 1)d$, we get $a_7 = a + 6d \implies 4 = a + 6(-4) \implies 4 = a - 24 \implies a = 28$. Hence, option D is correct.
Detailed Options Breakdown
Option : 12
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Arithmetic Progressions.
Option 1: 20
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Arithmetic Progressions.
Option 2: 24
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Arithmetic Progressions.
Option 3: 28 (Correct Answer)
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
💡 Study Guide: This question tests core syllabus concepts from Arithmetic Progressions. For formulas, key summaries, and mock exam reference guides, read the full Arithmetic Progressions Revision Notes.