 
 <translate> The question: Two pipes can fill a tank in 20 and 12 hours, while third pipe will make the tank empty in 20 hours. If all three pipes operate simultaneously. In how many hours the tank will be filled ?
Options:
(A) 5 Hours
(B) 7 Hours
(C) 8 Hours
(D) 9 Hours
(E) 12 Hours <ibo> Ajụjụ ahụ bụ: Ọ bụ ọkpọkọ abụọ ga-eme ka mmiri jupụta n'ime awa iri abụọ na awa iri na abụọ, ebe ọkpọkọ nke atọ ga-eme ka mmiri gbapụ n'ime awa iri abụọ. Ọ bụrụ na ọkpọkọ atọ ahụ na-arụ ọrụ n'otu oge. Awa ole ka ọ ga- ewe iji gbajuo ya? Nhọrọ: (A) Awa ise (B) Awa 7 (C) Awa 8 (D) Awa 9 (E) Awa iri na abụọ 