Chaining ratios across three persons The ratio of money with Ram and Gopal is 7 : 17, and the ratio with Gopal and Krishan is 7 : 17. If Ram has ₹ 490, how much money does Krishan have?

Introduction / Context:
When two pairwise ratios share a common person, we can “chain” them by equalizing the common term to derive a three-person ratio. Then actual amounts follow by scaling to a given person’s value.

Given Data / Assumptions:

• Ram : Gopal = 7 : 17.
• Gopal : Krishan = 7 : 17.
• Ram has ₹ 490.

Concept / Approach:
Make Gopal’s parts in both ratios equal. LCM(17, 7) = 119, so scale the first ratio by 7 and the second by 17 to set Gopal = 119 parts in both. Then read off Ram and Krishan’s parts and scale to rupees using Ram’s given amount.

Step-by-Step Solution:
Scaled Ram:Gopal = 7*7 : 17*7 = 49 : 119.Scaled Gopal:Krishan = 7*17 : 17*17 = 119 : 289.Combined three-way ratio: Ram : Gopal : Krishan = 49 : 119 : 289.Given Ram = ₹ 490 ⇒ 49 parts = 490 ⇒ 1 part = ₹ 10.Krishan = 289 parts = 289 * 10 = ₹ 2,890.

Verification / Alternative check:
Gopal = 119 * 10 = ₹ 1,190; then Ram:Gopal = 490:1,190 simplifies to 7:17, and Gopal:Krishan = 1,190:2,890 simplifies to 7:17, confirming consistency.

Why Other Options Are Wrong:
Other rupee amounts do not maintain both pairwise ratios when combined with Ram = ₹ 490.

Common Pitfalls:
Adding ratios or averaging them. The correct technique is to equalize the common person’s parts before forming the combined ratio.

Final Answer:
Rs. 2890