Answer:
His friend took one from 61 and added it to 39. That made it easy to mentally add 40 and 60 to get 100. Then he mentally added 28 to 100 to get 128.
Answer:
The equation could be used to find the dimensions of the window would be:
Step-by-step explanation:
as
- The length of a rectangular window is 5 feet more than its width, w.
and
- The area of the window is 36 square feet.
So it means




Therefore, the equation could be used to find the dimensions of the window would be:
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, 
Answer:
q = 36/7 or 5 1/7
Step-by-step explanation:
q · 7/9 = 4
Multiply each side by 9/7
q · 7/9 *9/7 = 4*9/7
q = 36/7
If we want it as a mixed number instead of an improper fraction
7 goes into 36 5 times with 1 left over
q = 5 1/7