Super Rite Corp., a Harrisburg, Pa.-based grocery wholesaler, yesterday reported a 76 percent gain in profits for the nine months that ended in November. Sales rose 13.9 percent.

Super Rite owns the Basics chain in the Baltimore area. It also has stores in Pennsylvania, New Jersey, Delaware, Virginia and West Virginia.

The company attributed the gains to a new supply agreement with Shoppers Food Warehouse Corp., a chain of 29 high-volume supermarkets in the Washington area.

Three months ended 11/30/91

.. .. Revenue.. .. ..Net.. .. .. .Share

'91..305,153,000.. .2,452,000.. .0.20

'90..248,478,000.. .1,607,000.. .0.14

% change.. .+22.8.. .. .. +52.6.. +42.9

Nine months ended 11/30/91

.. .. .Revenue.. .. .Net.. .. .. .Share

'91.. .813,274,000.. 5,703,000.. .0.39

'90.. .713,815,000.. 3,241,000.. .0.20

% change.. . +13.9.. .. .+76.0.. .+95.0