<PRE><B>Question 815308</B>
a)  (28/45) / 28  tells us how much each worker contributes to the work
    let x be the number of workers required to complete the same amount of work in 36 days, therefore
let u = ((28/45) / 28)
u * 28 * 45 = u *x *36
cancel the u from both sides of the =
28*45 = 36x
x = 35 workers
b) (u * 28 *33) + (u * 21 * x) = (u * 28 * 45)
cancel u from both sides of =
(28*33) + 21x = 28*45
21x = 336
x = 16
rest of workers take 16 days to finish the job

 
   
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