In what ratio must rice costing ₹26 per kg be mixed with rice costing ₹54 per kg, so that the mixture is worth ₹48 per kg?

💡 Solution & Explanation

Use alligation: the cheaper part : the dearer part = (dearer price − mixture price) : (mixture price − cheaper price) = (54 − 48) : (48 − 26) = 6 : 22, which simplifies to 3 : 11. Check: mixing in that ratio gives an average of ₹48 per kg. Writing the differences the other way round is the most common mistake.