A. 18 is 20 percent of what number? B. 15 is 25 percent of what number? C. 12 is 30 percent of what number? D. 24 is 40 percent
of what number? E. 39 is 60 percent of what number? F. 78 is 30 percent of what number? Question: Represent each as an equation with x as the unknown number, and solve.