There are two types of counters in Japanese language. One of them,hitotsu, futatsu, mittsu type is a Japanese original counter and the other, ichi, ni, san type is Chinese one. Japanese type can be used independently used from
1to 10 only but Chinese type can be used number and counter together like
Japanese type---Three hamburgers, please. Hambaagaa o mittsu kudasai.
Chinese type --- Three hamburgers, please. Hambaagaa o san-ko kudasai.