 
<translate> Kwuo otú e si atụgharị uche n'isiokwu ahụ, kọwaa nke ọ bụla n'ime ha, ma kwuo ihe bụ azịza ya. Cameron nọ na-ebipụta ihe odide ya n'ọ́bá akwụkwọ ụlọ akwụkwọ ma nwee mpempe akwụkwọ A4 400. Ọ bụrụ na 40% nke akwụkwọ adịghị ebipụta ruo ya chọrọ àgwà na ọ kewara ha dị ka ghara ịdị irè, gbakọọ ngụkọta ọnụ ọgụgụ nke nti akwụkwọ. <eng> Give the step-by-step reasoning process and then the final answer. Cameron is printing her thesis in the school library and has 400 A4 pieces of paper. If 40% of the papers did not print out up to her desired quality and she separated them as invalid, calculate the total number of valid documents. 