Out of the total production of iron from hematite, an ore of Iron, 20% of the ore gets wasted, and out of the remaining iron, only 25% is pure iron. If the pure iron obtained in a year from a mine of hematite was 80,000 kg, then the quantity of hematite mined from that mine in the year is	Choices: A) 5,00,000 kg B) 4,00,000 kg C) 4,50,000 kg D) None of these E) Cannot be determined
Solution: Let 100 kg of hematite be obtained then 20% of it get wasted that means 80 kg of ore remains.   Pure iron = 25% of remaining ore = 80*25/100= 
<gadget id="calculator">80*25/100</gadget>
<output>20</output>
20 kg.   20 kg pure Iron is obtained from 100 of hematite.   1 kg pure Iron is obtained from= 100/20 hematite;   Then, 80000 kg pure Iron is obtained from = (100/20)*80000= 
<gadget id="calculator">(100/20)*80000</gadget>
<output>400_000</output>
400000 kg hematite.   Answer: Option 4,00,000 kg
<result>B</result>
Out of the total production of iron from hematite, an ore of Iron, 20% of the ore gets wasted, and out of the remaining iron, only 25% is pure iron. If the pure iron obtained in a year from a mine of hematite was 80,000 kg, then the quantity of hematite mined from that mine in the year is