Question

Help?

Answer 1

30 people are working on a project. They plan to finish in 15 days. After working for 4 days, they add 3 more people to help. If each person works the same amount, how many days ahead of time can they finish the project?

Answer 2

Anyone?

Answer 3

ok you need to look at the avg rate each person is working at

so if it takes 30 people 15 days to complete 100% of project, that is rate of 1/15
for 1 person it would take 30*15 = 450 days to complete project, that is rate of 1/450

now when 3 more people join the total rate of work increases to 33/450
rate * time = %project (work done)

after 4 days --> (1/15)*4 = 4/15 of project is done leaving 11/15 left to finish
now solve for time it takes 33 people to complete 11/15 of project
--> (33/450)*time = 11/15
--> time = 10

so total time 10+4 = 14 , adding 3 people caused project to finish 1 day ahead of time

Answer 4

Great, thank you so much!!

Answer 5

yw