SOLUTION: 12 men took 8 hour and 40 min to complete a job a. Find the time taken for 8 men to complete the job, working at the same rate b. if 2 of the 8 men left the job after working for

Algebra ->  Rate-of-work-word-problems -> SOLUTION: 12 men took 8 hour and 40 min to complete a job a. Find the time taken for 8 men to complete the job, working at the same rate b. if 2 of the 8 men left the job after working for      Log On


   

Question 940651: 12 men took 8 hour and 40 min to complete a job
a. Find the time taken for 8 men to complete the job, working at the same rate
b. if 2 of the 8 men left the job after working for just 1 hour. find the time taken for the remaining 6 men working at the same rate
Found 2 solutions by josgarithmetic, ankor@dixie-net.com:
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
r, the rate of work for 1 man, in JOB per HOURS

Initial description for the 1 job is 12%2Ar%2A8%262%2F3=1. The factor 12 is for 12 men instead of just 1 man.


(a):
t, time for 8 men to do the 1 job.
8r%2At=1;
highlight_green%288r%2At=12r%2A8%262%2F3%29.
Solve for t.

(b):
Maybe you can solve this yourself. You will have a sum of terms.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
12 men took 8 hour and 40 min to complete a job
Change 8 hr 40 min to 8.667 hrs
Find how many man-hrs required to complete the job
12 * 8.667 = 104 man-hrs
:
a. Find the time taken for 8 men to complete the job, working at the same rate.
let t = time required by 8 men
8t = 104
t = 104/8
t = 13 hrs
:
b. if 2 of the 8 men left the job after working for just 1 hour, find the time taken for the remaining 6 men working at the same rate.
let t = time taken by the remaining 6 men to complete the job
8 men worked for the 1st hr
8(1) + 6t = 104
6t = 104 - 8
6t = 96
t = 96/6
t = 16 more hrs worked by the remaining 6 men