In a case in which the defendant was convicted of trafficking in more than 400 grams of cocaine, the trial court did not err by allowing the State’s expert to testify that the substance was cocaine where the expert combined three separate bags into one bag before testing the substance. After receiving the three bags, the expert performed a preliminary chemical test on the material in each bag. The test showed that the material in each bag responded to the reagent in exactly the same manner. She then consolidated the contents of the three bags into a single mixture, performed a definitive test, and determined that the mixture contained cocaine. The defendant argued that because the expert combined the substance in each bag before performing the definitive test, she had no basis for opining that each bag contained cocaine, that all of the cocaine could have been contained in the smallest of the bags, and thus that he could have only been convicted of trafficking in cocaine based upon the weight of cocaine in the smallest of the three bags. Relying on State v. Worthington, 84 N.C. App. 150 (1987), and other cases, the court held that the jury should decide whether the defendant possessed the requisite amount of cocaine and that speculation concerning the weight of the substance in each bag did not render inadmissible the expert’s testimony that the combined mixture had a specific total weight.