In an action to recover the balance due under a contract for the sale of a business, the defendant appeals from a judgment of the Supreme Court, Nassau County (Morrison, J.), entered August 9, 1989, which, after a nonjury trial, is in favor of the plaintiffs and against it in the principal sum of $53,805.14.
Ordered that the judgment is affirmed, with costs.
We disagree with the defendant’s contention that the plaintiffs failed to meet their burden of proving the key element of the formula necessary to compute the purchase price as provided under the contract. The plaintiffs sustained their burden of proving the balance of the purchase price due them under the contract by a fair preponderance of the evidence (see, Richardson, Evidence §§ 95, 97 [Prince 10th ed]). At trial, *590as part of the plaintiffs evidence in chief, the defendant corporation’s Secretary/Treasurer testified, based upon the corporation’s business records, that the number of gallons of oil sold to the plaintiffs’ former customers by the defendant the first year after execution of the contract was 696,336.8 gallons. As provided by agreement of the parties, the number of gallons sold, multiplied by 13.5^, plus $23,500 for certain trucks delivered constituted the purchase price of the business.
We have reviewed the defendant’s remaining arguments, including those directed to the Supreme Court’s rejection of all but the first of its counterclaims, and find that they are either unpreserved for appellate review or without merit (CPLR 3211 [e]; Merryman v Gottlieb, 99 AD2d 893). Mangano, P. J., Bracken, Kunzeman and Kooper, JJ., concur.