Question
Two metal alloys 'M' and 'N' have gold and silver in the
ratio of 5:2 and 7:3 respectively. If 112 grams of M and 150 grams of N are mixed together, then find the ratio of gold to silver in the final mixture.Solution
Quantity of gold in 112 grams 'M' = 112 × (5/7) = 80 grams
Quantity of silver in 112 grams 'M' = 112 - 80 = 32 grams
Quantity of gold in 150 grams 'N' = 150 × (7/10) = 105 grams
Quantity of silver in 150 grams 'N' = 150 - 105 = 45 grams
So, required ratio = (80 + 105) : (32 + 45) = 185 : 77
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