Navaneet has three times as much money as Poonam. Poonam has 25% more money than Hebah. If the average amount of money held by Navaneet, Poonam and Hebah is Rs. 350, how much money does Navaneet have?

Introduction / Context:
This problem combines average calculations with percentage and ratio relationships between the amounts of money held by three people. It tests your ability to express values in terms of a single variable and then use the given average to determine the actual amounts for each person, especially the one with the largest share.

Given Data / Assumptions:

• Let Hebah's money be H rupees.

• Poonam has 25% more than Hebah, so Poonam's money = H + 25% of H.

• Navaneet has three times as much as Poonam.

• The average money of the three people is Rs. 350.

• We need Navaneet's amount of money.

Concept / Approach:
First, we express the money of each person in terms of H. Then we add these expressions to find the total amount of money for all three people. Since the average is given, total money = 3 * average. Setting our expression for the total equal to this value lets us solve for H. Once we know H, we can compute Poonam's money and then Navaneet's money, which is three times Poonam's amount.

Step-by-Step Solution:
Let Hebah's money = H. Poonam has 25% more than Hebah, so Poonam's money = H + 0.25H = 1.25H = 5H / 4. Navaneet has three times Poonam's money, so Navaneet's money = 3 * (5H / 4) = 15H / 4. Total money of three people = H + 5H / 4 + 15H / 4. Combine over a common denominator: H = 4H / 4, so total = (4H + 5H + 15H) / 4 = 24H / 4 = 6H. Average money = total / 3 = (6H) / 3 = 2H. Given average = Rs. 350, so 2H = 350, hence H = 175. Poonam's money = 1.25 * 175 = Rs. 218.75. Navaneet's money = 3 * 218.75 = Rs. 656.25.

Verification / Alternative check:
Check the total money: Hebah has Rs. 175, Poonam has Rs. 218.75 and Navaneet has Rs. 656.25. Total = 175 + 218.75 + 656.25 = 1050. Dividing by 3 gives 1050 / 3 = 350, which matches the given average. The ratios also hold: Poonam has 25% more than Hebah because 175 * 1.25 = 218.75, and Navaneet has three times Poonam's money because 3 * 218.75 = 656.25.

Why Other Options Are Wrong:
Any other figure for Navaneet's money would change the total and therefore the average. For example, if Navaneet had only Rs. 175, the sum and resulting average would be far lower than Rs. 350. The other decimal figures in the options do not satisfy the relationships or the total sum requirement. Only Rs. 656.25 is consistent with both the given average and the stated relationships between the three amounts.

Common Pitfalls:
Mistakes often occur in handling the percentage increment or in converting 25% to a fraction. Some students also forget that the average of three people means the total is three times the average. Carefully organizing the relationships in terms of a single variable and working step by step helps prevent algebraic errors.

Final Answer:
Navaneet has Rs. 656.25.