Ametal alloy that is made up of 15% aluminum is combined with a metal alloy that is 35% aluminum. if the result is 400 kilograms of 27.5% of aluminum alloy, then how much of each alloy was used?

1. Assume that the types of metal allow we use are type A and type B

2. Assume we are using x kg of A and y kg of B

3. Then x+y=400, so y=400-x

also the weight of the aluminium in x kg of A and y kg of B are respectively:

and



so the total sum of the aluminium is  

4. 27.5% of 400 is  kg 

5. 

     



x=150 (kg), 

y=400-x=400-150=250(kg)