Final answer:
If Zeru can complete a job in 5 days and Tulu can complete the same job in 3 days, they can complete the job together in approximately 1 day and 21 hours.
Step-by-step explanation:
If Zeru can complete a job in 5 days and Tulu can complete the same job in 3 days, we can determine their individual rates of work. Zeru can complete 1/5 of the job in 1 day, and Tulu can complete 1/3 of the job in 1 day.
To determine how long it would take if they work together, we can add their rates of work. Zeru's rate of work is 1 job/5 days, and Tulu's rate of work is 1 job/3 days. Combined, their rate of work is (1/5 + 1/3) jobs per day.
To find the time it takes for them to complete the job together, we can calculate the reciprocal of their combined rate. Therefore, it would take them 1/(1/5 + 1/3) = 1/(3/15 + 5/15) = 1/(8/15) = 15/8 = 1.875 days or approximately 1 day and 21 hours if they work together.