where did the number 0.198x come from?

Step1 Calculation of revenue to be earned by Bryan Bessner in order to meet all the costs and allow for expected after-tax return. Let the revenue to be earned be "x" Then the statement of after-tax income can be shown as below: Now, his after tax income =10% * investment as he wants after tax return of 10% Therefore, the equation would be: 0.198x$471,000=10%$600,0000.198x=$60,000+$471,000x=$531,000/0.198x=$2,681,818 Therefore, revenue to be earned (x)=$2,681,818