The equation given in the question is
13 + (w/7) = - 18
(91 + w) / 7 = - 18
91 + w = - 126
w = - 126 - 91
= - 217
I hope that the procedure is clear enough for you to understand. I also hope that this is the answer that you were looking for and the answer has actually come to your desired help.
Answer:
1: L = 5
W = 7
2: A = lw
3: 35
4: 18
5: You have to add them up because it is 1 shape broken up into different parts.
6: 53
You are adding 18%, which makes it 118% of original employees
Times 450 by 1.18 = 531