How many sevenths are there in two wholes?

Abacteria population is tripling every hour. by what factor does the population change in 1/2 hour? select all that apply

(60 points) explain this in detail

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?