Two barrels contain a mixture of ethanol and gasoline. The content of ethanol is 60% in the first barrel and 30% in the second barrel. In what ratio must the mixtures from the first and the second barrels be taken to form a mixture containing 50% ethanol?

Using the rule of alligation, the percentage of ethanol in the first barrel is 60 and in the second barrel is 30, while the desired percentage is 50. The differences between the desired percentage and the given percentages are 10 for the first barrel and 20 for the second barrel. The required ratio is the inverse of these differences, which is 20 : 10. The mixtures must be taken in the ratio 2 : 1.

• Thanks
• Wrong explanation