Ihave trouble finding the nth term of a linear sequence

Michael is training for a marathon. in his first week he plans to run 8miles. what path should he take

Aphrase is shown read the phrase and give me the answer

Ateacher wanted to buy a chair, a bookshelf, two tables and a desk. she spent $900 for all five items and the chair and the desk combined 70% of her total. if the bookshelf cost $50, how much did each of the tables cost?