Respuesta :
Using an inverse rule of three, it is found that Bobby needs to call 18 more people.
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- This question is solved by proportions, applying a rule of three.
- The number of people working and the time needed to complete the work are inversely proportional, as more people means less time, thus, instead of cross multiplication, we multiply the lines, which is an inverse rule of three.
- When Bobby's parents call, with 9 people, they will need 6 hours to finish the job. How many people are needed to finish the job in 2 hours?
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The rule of three is:
9 people - 6 hours
x people - 2 hours.
Multiplying by line:
[tex]2x = 6(9)[/tex]
[tex]2x = 54[/tex]
[tex]x = \frac{54}{2}[/tex]
[tex]x = 27[/tex]
Already has 9 people, in total needs 97, so he needs to call 27 - 9 = 18 more people.
A similar problem is given at https://brainly.com/question/21325349
Here, we are required to determine how many more friends does Bobby need to call for help to finish cleaning in time.
Bobby needs 18 more friends to help finish the cleaning in time.
The question above can be solved by ratios and proportions: As such;
Since 9 friends can finish in 8 hours;
After 2 hours, they must have completed 25 % (i.e 1 quarter of the job).
As such, the 9 friends now need 6 hours to complete the rest of the cleaning.
However, since the parents are now 2 hours from home;
Let the number of friends Bobby needs to complete the job in 2 hours be x.
Since;
9 friends take 6hours to complete the cleaning,
then, In 2 hours, Bobby needs, x = (9×6)/2 friends to complete the job.
Ultimately, Bobby needs 27 friends to complete the cleaning in 2 hours.
However, since Bobby has 9 friends on the cleaning already, he needs (27 - 9) = 18 friends more to complete the cleaning in 2 hours.
Read more:
https://brainly.com/question/14457765