It will take them 2 hours and 22 minutes to working together.
Here,
Joan paint the porch in 5 hours.
Jan can take 4 hours to paint the porch.
We have to find the time to take them working together.
What is Fraction?
A fraction simply tells us how many parts of a whole we have.
Now,
Let x is number of hours to take them working together.
Then, 1/x is how much of the porch they can paint together in 1 hour.
Joan paint the porch in 5 hours.
Then, Joan can take 1 hour to paint the 1/5 part of porch.
Jan can take 4 hours to paint the porch.
Then, Jan can take 1 hour to paint the 1/4 part of porch.
To find how much of the porch they can paint together in 1 hour, we can add together;
[tex]\frac{1}{5}+ \frac{1}{4} = \frac{1}{x} \\\\\frac{4+5}{20} = \frac{1}{x} \\\\\frac{9}{20} = \frac{1}{x}\\\\x = 20.22[/tex]
Hence, It will take them 2 hours and 22 minutes to working together.
Learn more about the fraction visit:
https://brainly.com/question/17220365
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