Question
A storeroom has only steel and copper rods in the ratio
8:7, respectively and the weight of each steel and each copper rod is in the ratio 3:7, respectively. If the total weight of all the rods in the storeroom is 219 kg, then what is the weight of one steel rod?Solution
Let the number of steel and copper rods in the storeroom be β8kβ and β7kβ, respectively Let the weight of one steel rod and one copper rod be β3yβ kg and β7yβ kg, respectively According to the question, 8k Γ 3y + 7k Γ 7y = 219 Or, 24ky + 49ky = 219 Or, 73ky = 219 Or, ky = (219/73) = 3 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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