Question
The cost of a piece of diamond varies with the square of
its weight. A diamond of Rs.9720 value is cut into 3 pieces whose weights are in the ratio 4: 3: 2. Find the loss involved in the cutting.Solution
Let cost = k(weight)² so, 9720 = k (4+3+2) ² 9720 = k×81 k = 9720/81 = 120-----(1) so now the new cost - C= C1 + C2 + C3 =K(w₁) ²+k(w₂) ²+k(w₃) ² =k (16+9+4) =120×29=3480 loss =9720-3480=6240
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