0.625 is the answer hope that hepled
2x+y=3
- x+y=5
---------------
x=-2
2(-2)+y=3
y=7
-2+y=5
y=7
(-2,7)
Answer: 3.4 h
Explanation:
1) The basis to solve this kind of problems is that the speed of working together is equal to the sum of the individual speeds.
This is: speed of doing the project together = speed of Cody working alone + speed of Kaitlyin working alone.
2) Speed of Cody
Cody can complete the project in 8 hours => 1 project / 8 h
3) Speed of Kaitlyn
Kaitlyn can complete the project in 6 houres => 1 project / 6 h
4) Speed working together:
1 / 8 + 1 / 6 = [6 + 8] / (6*8 = 14 / 48 = 7 / 24
7/24 is the velocity or working together meaning that they can complete 7 projects in 24 hours.
Then, the time to complete the entire project is the inverse: 24 hours / 7 projects ≈ 3.4 hours / project.Meaning 3.4 hours to complete the project.
