There are 2 alloys, one contains 5% nickel, the second 25% nickel, from these alloys a third alloy with a mass of 150 kg

There are 2 alloys, one contains 5% nickel, the second 25% nickel, from these alloys a third alloy with a mass of 150 kg was obtained, containing 20% nickel, how much is the mass of the first alloy less than the mass of the second alloy?

Let’s designate: y kg – mass of the first alloy. This means that the mass of the second alloy is 150 – y kg.
According to the condition of the problem, an equation was drawn up:
0.05y + 0.25 * (150 – y) = 0.2 * 150;

0.05y + 37.5 – 0.25y = 30;

0.05y – 0.25y = 30 – 37.5;

-0.2y = -7.5;

y = -7.5 / (-0.2);

y = 37.5;

If y = 37.5, then 150 – y = 150 – 37.5 = 112.5.

Let’s find the mass difference between the alloys:
112.5 – 37.5 = 75 kg;

Answer: the mass of the first alloy is 75 kg less than the mass of the second alloy.