look at the graph for full-time employees first. Add up the number of employees: 20+40+50=110 there are altogether 110 full-time employees, and 110 is 55% of the total number of employee part-time employee is 45%, so 45%:x=55%:110, x=90 there are a total of 90 part-time employees for question #27, the answer is 110-90=20, a is correct for question #28, 60% of 90=54, d is correct.