CBSE · Class 8 · Mathematics · Direct and Inverse ProportionsIf 15 pens cost ₹ 75, what is the cost of 1 graph of direct proportion? Find the cost of 10 pens.
Step-by-Step Solution
Let the cost of 10 pens be $x$. Since the number of pens and cost are in direct proportion, $\frac{15}{75} = \frac{10}{x}$. Solving gives $x = \frac{10 \times 75}{15} = 50$.
Detailed Options Breakdown
Option : ₹ 40
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Direct and Inverse Proportions.
Option 1: ₹ 50 (Correct Answer)
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
Option 2: ₹ 60
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Direct and Inverse Proportions.
Option 3: ₹ 45
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Direct and Inverse Proportions.
💡 Study Guide: This question tests core syllabus concepts from Direct and Inverse Proportions. For formulas, key summaries, and mock exam reference guides, read the full Direct and Inverse Proportions Revision Notes.