Sal and Yuri's Job

Question

Sal can complete a job in 100 minutes working alone. Yuri can complete the same job in 120 minutes. If they work together. what percentage of the job would they finish in 30 minutes?

Answer 1

What percentage of the job would they finish in what amount of time?

Are you looking for the amount of time it would take them to complete the entire job working together?

 

Sal:  1/100 of the job per minute

Yuri:  1/120 of the job per minute

Together:  1/100 + 1/120 = 6/600 + 5/600 = 11/600 of the job per minute

 

(11/600)m = 1

m = 600/11

m = 54.545 minutes to complete the job working together