—Final order of disposition, Family Court, New York County (Bruce Kaplan, J.), entered June 10, 1993, which adjudicated appellant a *274juvenile delinquent based on a fact-finding determination based upon appellant’s admission, and placed him in custody of New York State Division for Youth, unanimously reversed, on the law, the fact-finding determination vacated and the petition dismissed, without costs.
Appellant contends, respondent concedes, and we agree that the adjudication of appellant as a juvenile delinquent is constitutionally infirm and must be reversed. The fact-finding determination, based upon appellant’s admission of the allegations in the fifth count of the petition, must be vacated because the Family Court Judge did not adequately determine whether appellant, given his intellectual limitations, understood the rights which he was waiving concerning the voluntariness of his admission. The court also failed adequately to apprise appellant of the possible dispositional orders (Family Ct Act §§ 320.3, 321.3 [1]).
We also find that the provisions of Family Court Act § 340.1 were violated by the adjournment of the fact-finding hearing on two occasions for periods in excess of 30 days, necessitating the dismissal of the petition (see, Matter of Randy K., 77 NY2d 398; Matter of Frank C., 70 NY2d 408). Concur — Rosenberger, J. P., Asch, Rubin, Williams and Tom, JJ.