0.85
68/80 = 17/20
Just used a calculator lol<span />
The answer is: 90 you can calculate this: 900/10=90
4 walls need 262 people/minutes (7)(36)
1 wall takes 63 people/minutes (262/4)
7 walls need 441 people/minutes (63)(7)
9 people could do that in 49 minutes (441/9)
HOPE THIS HELPS!!!!
First, plug Y into the equation
16=-5x+4
Get variables on one side and numbers on the other
Subtract 4 from both sides
12=-5x
X= 12/5