Question

Adam can do a job in 10 days, while brenda takes 15 days to do it. after brenda works alone for 3 days, adam and brenda work together to finish the job. how many days did adam work?

Answer 1

= [1- (3/15)]/(1/10 + 1/15)
= (4/5)÷(1/6)
= 24/5
= 4 4/5