The cost of a piece of diamond varies with the square of its weight. A diamond of Rs. 6,084 value is cut into 3 pieces whose weights are in the ratio 3 ∶ 2 ∶ 1. Find the loss involved in the cutting.
Rs. 3,718
The problem states that the cost of a piece of diamond varies with the square of its weight. This means if the weight is \(W\), the cost \(C\) can be expressed as \(C = k W^2\), where \(k\) is a constant value.
We are given an original diamond with a value of Rs. 6,084. Let its original weight be \(W_{\text{original}}\). So, the initial condition is:
\(6084 = k (W_{\text{original}})^2\)
The original diamond is cut into three pieces. The weights of these three pieces are in the ratio 3 ∶ 2 ∶ 1. Let the common ratio factor be \(w\). Then the weights of the three pieces are \(3w\), \(2w\), and \(w\).
The total weight of the three pieces must be equal to the original weight of the diamond before cutting. So,
\(W_{\text{original}} = 3w + 2w + w = 6w\)
Now we can substitute the total weight \(W_{\text{original}} = 6w\) back into the original cost equation:
\(6084 = k (6w)^2\)
\(6084 = k \times 36w^2\)
From this equation, we can find the value of \(kw^2\), which will be useful in calculating the cost of the individual pieces:
\(kw^2 = \frac{6084}{36}\)
Performing the division:
\(6084 \div 36 = 169\)
So, \(kw^2 = 169\).
Now, let's calculate the value of each of the three pieces using the cost-weight relationship \(C = k W^2\) and the fact that \(kw^2 = 169\).
The total value of the diamond after it has been cut into three pieces is the sum of the values of the individual pieces:
Total value after cutting = \(C_1 + C_2 + C_3\)
Total value after cutting = \(9 (kw^2) + 4 (kw^2) + (kw^2)\)
Total value after cutting = \((9 + 4 + 1) (kw^2)\)
Total value after cutting = \(14 (kw^2)\)
Substitute the value \(kw^2 = 169\):
Total value after cutting = \(14 \times 169\)
Let's calculate \(14 \times 169\):
| Calculation | Result |
|---|---|
| \(14 \times 100\) | 1400 |
| \(14 \times 60\) | 840 |
| \(14 \times 9\) | 126 |
| Total sum | \(1400 + 840 + 126 = 2366\) |
So, the total value of the diamond pieces after cutting is Rs. 2,366.
The loss involved in cutting the diamond is the difference between the original value of the diamond and the total value of the pieces after cutting.
Loss = Original value - Total value after cutting
Loss = Rs. 6,084 - Rs. 2,366
Let's calculate the difference:
| Operation | Value |
|---|---|
| Original Value | 6084 |
| Total Value After Cutting | -2366 |
| Loss | 3718 |
The loss involved in the cutting is Rs. 3,718.
By understanding the relationship between the diamond's cost and the square of its weight, we calculated the value of the individual pieces after cutting and found the total value is significantly less than the original. The difference represents the loss.
| Concept | Explanation | Application in Problem |
|---|---|---|
| Cost-Weight Relation | Cost ∝ (Weight)\(^2\) i.e., \(C = k W^2\) | Used to relate original cost to original weight and piece costs to piece weights. |
| Weight Ratio | Weights in ratio 3:2:1 | Allows expressing individual weights as \(3w, 2w, w\) and total weight as \(6w\). |
| Constant of Proportionality (k) | Links cost and square of weight. | Calculated implicitly via \(kw^2\) value using original diamond data. |
| Total Value After Cutting | Sum of values of individual pieces. | Calculated as \(14 \times (kw^2)\). |
| Loss Calculation | Original Value - Total Value After Cutting | Found the difference between Rs. 6084 and Rs. 2366. |
This diamond cost problem is a good example of a concept called direct proportionality, specifically varying with the square of a quantity. Here's a bit more about proportional relationships:
Understanding how quantities relate through proportionality helps solve many problems in physics, economics, and other areas, including quantitative aptitude questions like this one.
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