Answer:
47/12, or 3 11/12
Step-by-step explanation:
9 1/2 - 5 7/12 > convert to improper fractions
19/2 - 67/12
make same denominator (12)
19/2 * 6 = 114/12
114/12 - 67/12 = 47/12
You are adding 18%, which makes it 118% of original employees
Times 450 by 1.18 = 531
