+26367 \(\begin{array}{rcll} 4 \text{ people} \cdot 2.5\ h &=& \frac12\ \text{job} \quad & | \quad \cdot 2 \\ 10\text { people} \cdot x &=& \frac13\ \text{job} \quad & | \quad \cdot 3 \\ \end{array}\\ \)
\(2\cdot 4 \cdot 2.5 = 1 job = 3\cdot 10 \cdot x\\ x = \frac{2\cdot 4 \cdot 2.5}{3\cdot 10}\ h\\ x = \frac{20}{30} \ h\\ x = \frac23\ h \\ x = 40\ \text{minutes} \)
.+26367 \(\begin{array}{rcll} 4 \text{ people} \cdot 2.5\ h &=& \frac12\ \text{job} \quad & | \quad \cdot 2 \\ 10\text { people} \cdot x &=& \frac13\ \text{job} \quad & | \quad \cdot 3 \\ \end{array}\\ \)
\(2\cdot 4 \cdot 2.5 = 1 job = 3\cdot 10 \cdot x\\ x = \frac{2\cdot 4 \cdot 2.5}{3\cdot 10}\ h\\ x = \frac{20}{30} \ h\\ x = \frac23\ h \\ x = 40\ \text{minutes} \)
+118608 Solveit,
You asked exactly the same question before.
And you were involved in the answers.
I do not understand why you asked again.
I am really puzzled by this.
+2498 i accidentally paste the same photo it was a percent question: "I can t understood your percents :/"
I like to look it as how many people-minutes/job (people minutes per job)
( 4 people x 150 minutes ) / (1/2 job) = 1200 people-minutes/job
for the second job: ( 10 people x ?minutes)/ (1/3job) = 1200 people-minutes/job
then ? = 40 minutes
+118608 Hi Solveit,
I do not understand, couldn't you delete the picture when you realized it was the wrong one?
I am not upset with you, I a m just trying to ascertain if there is something about the site that I don't understand.
I was only just told last night that normal members cannot edit their posts for very long after they are posted.
I didn't know that......
Oh, I see, that is what you were trying to tell us in your first answer post. Ok 
