 
<translate> Ka X bụrụ ọnụ ọgụgụ ụmụaka nọ n'ìgwè ahụ. Ọnụ ọgụgụ ndị okenye nọ n'ìgwè ahụ bụ X + 25. Òtù ahụ na-akwụ 8 * X + 15 * (X + 25) = $720. Ịba ụba site na parentheses, anyị na-enweta 8X + 15X + 375 = $720. Na ijikọta okwu ndị yiri ya, anyị na-enweta 23X + 375 = 720. Anyị wepụ 375 n'akụkụ abụọ, anyị na-enweta 23X = 720 - 375 = $345. Ịkewa akụkụ abụọ site na 23, anyị na-enweta X = $345 / 23 = ụmụaka 15. Azịza ikpeazụ ya bụ: 15. <eng> Let X be the number of children in the group. The number of adults in the group is X + 25. The group pays 8 * X + 15 * (X + 25) = $720. Multiplying through the parentheses, we get 8X + 15X + 375 = $720. Combining like terms, we get 23X + 375 = 720. Subtracting 375 from both sides, we get 23X = 720 - 375 = $345. Dividing both sides by 23, we get X = $345 / 23 = 15 children. The final answer: 15. 