Step-by-step explanation:
sorry I don't now but when I now I will tell you ok but mybe it 12×12×12
Let same number of hours = x,
since the salary earned is also the same, then
Salary of supervisor A = $25x
Salary of supervisor B = $20(30)+$30(x-30)
Equating
25x=600+30(x-30)
30x-25x=900-600
5x=300
x=60 hours
Check:
Salary of supervisor A = 25*60=1500
Salary of supervisor B = 20*30+30*(60-30)=600+900=1500, ok.
0.78
hope this helps, good luck! :)
Youre answer is D, you’re welcome
Answer:

Step-by-step explanation:
The Universal Set, n(U)=2092


Let the number who take all three subjects, 
Note that in the Venn Diagram, we have subtracted
from each of the intersection of two sets.
The next step is to determine the number of students who study only each of the courses.
![n(S\:only)=1232-[103-x+x+23-x]=1106+x\\n(F\: only)=879-[103-x+x+14-x]=762+x\\n(R\:only)=114-[23-x+x+14-x]=77+x](https://tex.z-dn.net/?f=n%28S%5C%3Aonly%29%3D1232-%5B103-x%2Bx%2B23-x%5D%3D1106%2Bx%5C%5Cn%28F%5C%3A%20only%29%3D879-%5B103-x%2Bx%2B14-x%5D%3D762%2Bx%5C%5Cn%28R%5C%3Aonly%29%3D114-%5B23-x%2Bx%2B14-x%5D%3D77%2Bx)
These values are substituted in the second Venn diagram
Adding up all the values
2092=[1106+x]+[103-x]+x+[23-x]+[762+x]+[14-x]+[77+x]
2092=2085+x
x=2092-2085
x=7
The number of students who have taken courses in all three subjects, 