Algebraic structures sometimes need to be typed. For example, matrices over real numbers form a ring, but multiplication is a only a partial operation: dimensions have to agree. Therefore, a natural way to look at the ring of matrices algebraically is to consider ``typed rings''. We prove several ``untyping'' theorems: in some algebras (semirings, Kleene algebras, residuated lattices, involutive residuated lattices), typed equations can be derived from the underlying untyped equations. As a consequence, the corresponding untyped decision procedures can be extended for free to the typed settings. Some of these theorems are obtained via a detour through fragments of cyclic linear logic.