One alloy contains 30% gold, the second alloy contains 55% gold. in what ratio should these alloys

One alloy contains 30% gold, the second alloy contains 55% gold. in what ratio should these alloys be taken to obtain a new alloy with a gold content of 40%

1. The first alloy of mass M1 contains 30% gold;

2. The second alloy with a mass of M2 contains 55% gold;

3. It is required to obtain an alloy M3 with a gold content of 40%;

4. Let’s compose the balance for gold of the original alloys and the new:

0.3 * M1 + 0.55 * M2 = 0.4 * (M1 + M2);

0.4 * M1 – 0.3 * M1 = 0.55 * M2 – 0.4 * M2;

0.1 * M1 = 0.15 * M2;

M1 / M2 = 0.15 / 0.1 = 3/2.

Answer: you need to take alloys in a ratio of 3/2.