Answer: r≈11.28
Step-by-step explanation:
Answer:
12 hours
Step-by-step explanation:
Let Theo's siste can paint a fence in x times
Given.
Theo can paint a fence three times as fast as his sister can. Working together, they can paint a fence in 9 hours.
![\frac{1}{x}+\frac{1}{3x} =\frac{1}{9}\\\frac{3+1}{3x} =\frac{1}{9} \\\frac{4}{3x}=\frac{1}{9}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bx%7D%2B%5Cfrac%7B1%7D%7B3x%7D%20%3D%5Cfrac%7B1%7D%7B9%7D%5C%5C%5Cfrac%7B3%2B1%7D%7B3x%7D%20%3D%5Cfrac%7B1%7D%7B9%7D%20%5C%5C%5Cfrac%7B4%7D%7B3x%7D%3D%5Cfrac%7B1%7D%7B9%7D)
Apply cross multiplication
![x=\frac{9\times 4}{3}\\x=\frac{36}{3} \\x=12hours](https://tex.z-dn.net/?f=x%3D%5Cfrac%7B9%5Ctimes%204%7D%7B3%7D%5C%5Cx%3D%5Cfrac%7B36%7D%7B3%7D%20%5C%5Cx%3D12hours)
Theo’s sister to paint the fence in 12 hours.
Answer:
7z
Step-by-step explanation:
4z-(-3z).
Two negatives equal a positive only <u>when they are right next to each other.</u>
4z+3z=7z. Hope this helps :D
Answer:
U=19
A=8
B=5
Step-by-step explanation:
Cardinality refers to the number of elements in a set.
The anwser to the problem is C.