Write a system of equations to describe the situation below, solve using substitution, and fill in the blanks. Two tailors, Danielle and Tammy, sit down to do some embroidery. Danielle can embroider 6 shirts per hour, and Tammy can get through 4 shirts per hour. In addition, the tailors had previously finished some shirts. Danielle has already completed 9 shirts, and Tammy has completed 11 shirts. Danielle and Tammy decide to take a break when they have finished the same total number of shirts. How many shirts, in total, will each tailor have finished? How long will that take?

Each tailor will have finished a total of shirts in hour