If you mean how many weeks total, 125 according to the 20 dollars a week would bring it 22 weeks i think.. since the answer answer is 21.2 weeks exactly when you divide 425 by 20.
Answer:if the notebooks cost 3.59 and pens cost 1.49, with x representing the notebooks and y representing the number of pens and an amount of $13, the inequality would be written as 3.59x+1.49y13