 
<translate> Onye meriri n'afọ gara aga riri hamburger 21 n'ihi na 84 / 4 = 21. Ọ dị mkpa ka o rie hamburger iri abụọ na abụọ n'ihi na iri abụọ na otu gbakwunyere otu bụ iri abụọ na abụọ. N'ihi ya, azịza ya bụ 22. <eng> Last year's winner ate 21 hamburgers because 84 / 4 = 21. She needs to eat 22 hamburgers because 21 + 1 = 22.
Therefore, the answer is 22. 