Answer:
If they work together, they take 48 minutes to line the football field.
Step-by-step explanation:
Given: Reggie can line a football field in 120 minutes. Rosalinda can line a football field in 80 minutes.
To find : If they work together, how many minutes does it take them to line a football field?
Solution :
If they work together,
Let the number of minutes(x) they take to line the foot ball field.
According to question,
[tex]\frac{1}{x}=\frac{1}{120}+\frac{1}{80}[/tex]
[tex]\frac{1}{x}=\frac{80+120}{120\times 80}[/tex]
[tex]\frac{1}{x}=\frac{200}{120\times 80}[/tex]
Cross multiply,
[tex]x=\frac{120\times 80}{200}[/tex]
[tex]x=12\times 4[/tex]
[tex]x=48[/tex]
Therefore, If they work together, they take 48 minutes to line the football field.
Answer: If they work together, they can line a football field in 48 minutes.
Step-by-step explanation: Given that Reggie can line a football field in 120 minutes and Rosalinda can line a football field in 80 minutes.
We are to find the number of minutes does it take them to line a football field if they work together.
We have
Time taken by Reggie to line a football field = 120 minutes.
So, in 1 minute, Reggie can line [tex]\dfrac{1}{120}[/tex] part of the field.
Time taken by Rosalinda to line a football field = 80 minutes.
So, in 1 minute, Rosalinda can line [tex]\dfrac{1}{80}[/tex] part of the field.
Therefore, if they work together, the portion of the football field that they can lie in 1 minute is given by
[tex]\dfrac{1}{120}+\dfrac{1}{80}\\\\\\=\dfrac{2+3}{240}\\\\\\=\dfrac{5}{240}\\\\\\=\dfrac{1}{48}[/tex]
Thus, if they work together, they can line a football field in 48 minutes.
