 
 <prompt> A tank nwere iji nwere 100 liters n'ụtụtụ mmiri. Na isi ụbọchị mmiri, tank nwere 2/5 nwere mmiri. Na ụbọchị mbu, tank jụ 15 liters mmiri. Na ụbọchị abụọ, jụ 5 liters mmiri nweta nke mbu. Na ụbọchị atọ, tank kwadoro jụ mmiri. Kama mmiri nwere jụ na ụbọchị atọ? <response>: N'ime iji nke mmiri, otu akpa na-akpọ 100 x 2/5 = 40 liteer nke mmiri.
N'ụbọchị mbu nke iji nke mmiri, akpa na-akpọ 40 + 15 = 55 liteer nke mmiri.
N'ọkara mbu, 15 + 5 = 20 liteer nke mmiri bụrụ na-akpọ.
N'ihi na-akpọ, akpa na-akpọ 55 + 20 = 75 liteer nke mmiri n'ọkara mbu.
N'ile, 100 - 75 = 25 liteer nke mmiri bụrụ na-akpọ n'ọkara mbu.

Ọ bụghị ya bụ 25. 