Derive the molecular formula of the island if it is known that the mass fraction of carbon is 37.21%

Derive the molecular formula of the island if it is known that the mass fraction of carbon is 37.21%, the mass fraction of hydrogen is 7.75%, and the mass fraction of chlorine is 55.04%.

Let us denote: x is the number of carbon atoms, y is the number of hydrogen atoms, z is the number of chlorine atoms, m is the molecular weight of the compound.
The relative atomic mass of carbon is 12, hydrogen is 1, chlorine is 35.5.
Let’s compose the following expressions:
0.3721 = 12 * x / m;

0.0775 = 1 * y / m;

0.5504 = 35.5 * z / m;

Let’s express the molecular weight:
m = 12 * x / 0.3721 = 32.25x;

m = 1 * y / 0.0775 = 12.9y;

m = 35.5 * z / 0.5504 = 64.5z;

The values of the unknown numbers: x = 2, y = 5, z = 1. The formula of the substance is C2H5Cl.

Answer: the molecular formula of the substance is C2H5Cl.