A solution is a homogeneous mixture of two or more substances. In a solution, the solute (the substance present in the lesser amount) is evenly distributed throughout the solvent (the substance present in greater amount).

Whereas, a mixture is a combination of two or more substances that are not chemically bonded. In a mixture, the substances retain their individual chemical properties, and the components of a mixture can be easily separated by physical means.

In the case of a cake mixture, it contains various ingredients such as flour, sugar, eggs, butter, baking powder, and flavorings, which are physically mixed together but not chemically bonded. Therefore, a cake mixture is considered a mixture rather than a solution.