Anna starts playing marbles with 5 small marbles which are worth 25 cents each and 8 large marbles which are worth k cents each. She trades 3 large marbles for 1 large marble and 6 small marbles. Finally, she gives Henry 4 small marbles. In cents, what is the value of the marbles she has left, in terms of k? Put your answer in form a+bk with integer values a and b.