The experienced window washer can wash all the windows in Mike’s house in 2 hours, which implies that in 1 hour he completes 1/2 of the job.
By the same logic, the new trainee completes 1/7 of the job in one hour.
If they work together, they complete
![\dfrac{1}{2}+\dfrac{1}{7}=\dfrac{7}{14}+\dfrac{2}{14}=\dfrac{9}{14}](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B2%7D%2B%5Cdfrac%7B1%7D%7B7%7D%3D%5Cdfrac%7B7%7D%7B14%7D%2B%5Cdfrac%7B2%7D%7B14%7D%3D%5Cdfrac%7B9%7D%7B14%7D)
of the job in one hour, meaning that they complete the job in 14/9 of a hour.
The <em>correct answers</em> are:
Top circle: 34
Bottom left: 9
Bottom right: 21
Explanation:
Let the top circle be x, let the bottom left circle be y, and the bottom right circle be z.
Following the diagram, we have the following equaitons:
x+y = 43
y+z = 30
x+z = 55
Taking the first two equations as a system, we will eliminate y:
![\left \{ {{x+y=43} \atop {z+y=30}} \right.](https://tex.z-dn.net/?f=%20%5Cleft%20%5C%7B%20%7B%7Bx%2By%3D43%7D%20%5Catop%20%7Bz%2By%3D30%7D%7D%20%5Cright.%20%20)
We will subtract the bottom equation from the top:
![\left \{ {{x+y=43} \atop {-(z+y=30)}} \right. \\ \\x-z=13](https://tex.z-dn.net/?f=%20%5Cleft%20%5C%7B%20%7B%7Bx%2By%3D43%7D%20%5Catop%20%7B-%28z%2By%3D30%29%7D%7D%20%5Cright.%20%20%5C%5C%20%5C%5Cx-z%3D13%20)
We will now take this and the last equation as a system; this time, we will eliminate z by adding the two equations:
![\left \{ {{x-z=13} \atop {+(x+z=55)}} \right. \\ \\2x=68](https://tex.z-dn.net/?f=%20%5Cleft%20%5C%7B%20%7B%7Bx-z%3D13%7D%20%5Catop%20%7B%2B%28x%2Bz%3D55%29%7D%7D%20%5Cright.%20%20%5C%5C%20%5C%5C2x%3D68%20)
Divide each side by 2:
2x/2 = 68/2
x = 34
Substitute this into the first equation:
x+y = 43
34+y = 43
Subtract 34 from each side:
34+y-34 = 43-34
y = 9
Substitute this into the second equation:
y+z = 30
9+z = 30
Subtract 9 from each side:
9+z-9 = 30-9
z = 21
Ausation<span> vs. </span>Correlation<span>. </span>Causation<span> at its simplest definition refers to determining the cause or reason for some sort of phenomenon. ... A </span>correlation<span> is simply a recognized </span>relationship between<span> two things or events, but it does not imply</span>causation<span>. Rather, in cases of </span>correlation<span>, one thing or event predicts another. hope it helps</span>
Yes, it is true. I hope I'm not helping you cheat....lol.