Question
A storeroom has only steel and copper rods in the ratio
5:6, respectively and the weight of each steel and each copper rod is in the ratio 4:7, respectively. If the total weight of all the rods in the storeroom is 248 kg, then what is the weight of one steel rod?Solution
Let the number of steel and copper rods in the storeroom be ‘4k’ and ‘5k’, respectively Let the weight of one steel rod and one copper rod be ‘8y’ kg and ‘7y’ kg, respectively According to the question, 4k × 8y + 5k × 7y = 268 Or, 32ky + 35ky = 268 Or, 67ky = 268 Or, ky = (268/67) = 4 But since we do not have information regarding the exact number of rods in the room, we cannot determine the exact weight of one steel rod.
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