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500 kg of ore contained a certain amount of steel. After the first blast furnace process, 200 kg of slag containing 12.5% of steel was removed. The percentage of steel in the remaining ore was found to be 20% more than the percentage in the original ore. How many kg of steel were there in the original 500 kg ore?

500 kg of ore contained a certain amount of steel. After the first blast furnace process, 200 kg of slag containing 12.5% of steel was removed. The percentage of steel in the remaining ore was found to be 20% more than the percentage in the original ore. How many kg of steel were there in the original 500 kg ore? Correct Answer 89.2 kg

Calculation:

Initially, ‘x’ kg of steel was there in 500 kg of ore.

Steel in 200 kg of removed slag = 200 × 12.5/100

⇒ 25 kg

The percentage of steel in the remaining ore was found to be 20% more than the percentage in the original ore.

∴ (x – 25)/300 = 120/100 × x/500

⇒ (x - 25)/3 = 12x/50

⇒ 50x – 36x = 1250

⇒ 14x = 1250

⇒ x = 89.2 kg

∴ 89.2 kg of steel were there in the original 500 kg ore. 

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