[conservative98]

Not two thirds 3/4 of the states are required.

3/4 = 38 states.

[conservative98]

2/3 states to propose.

3/4 states to ratify.

[Robert DeLong]

The Congress, whenever two thirds of both Houses shall deem it necessary, shall propose Amendments to this Constitution, or, on the Application of the Legislatures of two thirds of the several States, shall call a Convention for proposing Amendments, which, in either Case, shall be valid to all Intents and Purposes, as Part of this Constitution,

when ratified by the Legislatures of three fourths of the several States, or by Conventions in three fourths thereof

As I read that it takes 2/3 of the Congress, or 2/3, (34) of the state legislatures to convene a COS to vote on a Constitutional Amendment.

It becomes ratified and becomes an amendment when 3/4 of the states agree to the amendment. So I take that to mean 38 state legislatures have to agree to the amendment in both avenues available.

Thus 34 to convene COS, but 38 state legislatures to pass, for the amendment to become a part of the Constitution.