1. A company produces 120 water bottles total using stainless steel and plastic materials. If x represents the number of stainless steel bottles produced, the remaining bottles are plastic. Each stainless steel bottle requires 3 ounces of insulating material, and each plastic bottle requires 1.5 ounces. What expression represents the total number of ounces of insulating material required?
2. The total earnings (in dollars) of a freelance graphic designer can be modeled by the equation E = 600 + 150pj where p is the designer’s hourly pay rate (in dollars per hour) and j is the number of projects completed. What is the best interpretation of the number 150 in this equation?
3. In a chemical lab, a researcher noted that twice the volume of chemical x divided by the volume of chemical y was 4.25. Later, she found that the volume of chemical x divided by the product y x n x 2/5 was 8.5. Based on this, what is the value of n ?