Ratio, Rate and Speed - Calculating Rates and Quantities

\(5\) workers are employed for a construction project. Assume the project requires \(480\) worker-hours of work, each worker works \(8\) hours per day and earns an hourly rate of \(\$10\).

1. Find the number of days needed to complete the project and the total amount of money to be paid to the workers.
2. Is the total amount of money to be paid to the workers the same if the project manager employs \(5\) more workers to complete the project? State your reasons with detailed calculation.
3. Find the least number of additional workers that to be employed in order to complete the project in \(8\) days.

Overtime is paid at \(15\) dollars per hour for work beyond \(8\) hours per day.

4. Find the new total amount of money to be paid to the workers if the project needs to be completed in \(8\)days without employing more workers, i.e., complete with \(5\) workers. (Assume every worker works the same amount of time every day.)

Assume every worker maintains the same constant hourly work rate, with no efficiency loss when the workforce or daily hours change.