Answer:
<em>Worker B needs 9 days to finish the rest of the work</em>
Step-by-step explanation:
<u>Proportions</u>
Worker A finishes a project on his own in 12 days and worker B does the same in 16 days.
Worker A does 1/12 of the project in one day and worker B does 1/16 of the project in one day. When working together, they do

After 3 days they have completed:

parts of the project, this means it still remains:

parts of the project and it is done by B alone. Since B does
per day, he now takes

days to complete the project.
Worker B needs 9 days to finish the rest of the work
2x -3y = 13
4x -y = -9
Multiply the second equation by -3 to make the coefficient of Y opposite the first equation.
4x -y = -9 x -3 = -12x + 3y = 27
Now add this to the first equation:
2x -12x = -10x
-3y +3y = 0
13 +27 = 40
Now you have :
-10x = 40
Divide each side by -10:
x = 40 / -10
x = -4
Now you have a value for x, replace that into the first equation and solve for y:
2(-4) - 3y = 13
-8 - 3y = 13
Add 8 to both sides:
-3y = 21
Divide both sides by -3:
y = 21/-3
y = -7
Now you have X = -4 and y = -7
(-4,-7)
Answer:
Mean= 31
Step-by-step explanation:
To find the mean you need to add all the number together and then divide by how many ever numbers there are.
In this case
25 + 25 + 30 + 35 + 40=155
There are 5 numbers so you would divide by 5
155/5
=31