Answers:1.) The total number of hours required for Alvin to complete the entire work. 2.) ⅔ work completed and 2 ½ hours of work. 3.) Multiplication, Addition, and Division4.) The mixed number representing the time taken is converted to an improper fraction: 2 ½ = 2×2+1 ÷ 2 = 5/2 or 2 ½ hours.