(i) The application of general theory of distribution to wage fixation is the marginal productivity theory of wages.
(ii) According to the theory wages are determined by the marginal productivity of labour and equal to it at the point of equilibrium.
(iii) Under perfect competition wage is paid equal to marginal product of labour (wage = MPL). But in real world where there is imperfect competition, there is exploration of labour and wage is less than MPL.

Marshall has introduced the concept of "Quasi-rent" with regard to machines and other man-made appliances. According to Marshall, 'Quasi-rent is the income derived from machines and other applications for production by man".
There are some machines and other man-made appliances (e.g. boats) whose supply may be inelastic in the short run in relation to the demand for them. For example, when there is large increase in demand for fish during a season, the demand for boats will increase. But you cannot increase their supply over night. So they will earn some extra income over and above the normal income they receive. This, Marshall calls Quasi-rent. Quasi-rent will disappear, when once the supply of boats increases.

The Marginal productivity theory of profits: The theory is an application of the general theory of distribution. According to this theory, under perfect competition, profits will be equal to the value of the marginal product of organization.

1. The transaction Motive
2. The precautionary Motive
3. The speculative Motive