The cost of a precious stone varies as the cube of its weight. A certain precious stone broke into three pieces whose weights are in the ratio 1 : 2 : 3, as a result of which its cost reduces by Rs. 36,000. What was the cost of the stone before breaking?
Explanation:
Let the weights be x, 2x and 3x grams.
Previously, the weight of the stone was x + 2x + 3x = 6x gms
Cost of the stone before breaking = k(6x)³ = 216kx³
Cost of the stone after breaking = k[x³ + (2x)³ + (3x)³] = 36kx³
Now, 216kx³ - 36kx² = 36000
⇒ kx³ = 36000/180 = 2000
∴ 216kx³ = 216 × 2000 = Rs.4,32,000
Hence, option (b).
» Your doubt will be displayed only after approval.
Help us build a Free and Comprehensive Preparation portal for various competitive exams by providing us your valuable feedback about Apti4All and how it can be improved.