40 skilled employees need 60 days to complete a project while working

Question

40 skilled employees need 60 days to complete a project while working in the normal work schedule of 8 hours a day. They begin working but one month into the project, 30 employees need to shift to a different project. These 30 employees are replaced by 40 new employees who are 50% less productive. How much extra time per day should the new team work to avoid any delay in the completion of the project?

A. 10 hours 40 minutes
B. 10 hours 20 minutes
C. 6 hours 30 minutes
D. 2 hours 40 minutes
E. 2 hours 20 minutes

A. 10 hours 40 minutes
B. 10 hours 20 minutes
C. 6 hours 30 minutes
D. 2 hours 40 minutes
E. 2 hours 20 minutes

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AdarshSambare · Answer

Total work = 40 employees × 60 days × 8 hours = 19200 work units
Work done in first 30 days = 40 × 30 × 8 = 9600
Remaining work = 19200 − 9600 = 9600
After 30 days:
10 old employees remain (full productivity)
40 new employees at 50% productivity 
⇒ equal to 20 normal employees
Total effective employees = 10 + 20 = 30
Let new working hours per day = h
Remaining work must be done in 30 days:
30 × 30 × h = 9600
900h = 9600 
⇒ h = 10.67 hours 
= 10 hours 40 minutes
Extra time 
= 10h 40m − 8h 
=> 2h 40m
 Answer: D

BongBideshini · Answer

Let's take the rate of 1 skilled worker=> 1unit/hr
Total work
1unit/hr x 40 employees × 60 days × 8 hours
=  19200 units

Work done in the first 30 days
40 × 30 × 8
=  9600 units 
Remaining work = 19200 − 9600 =  9600 units

New team efficiency
 
 10 skilled =>10 units/hour 
 40 new (50% efficient) => 40 × 0.5 = 20 units/hour  
Total rate =  30 units/hour

Remaining days =  30 
Let hours/day = h
30 × h × 30 = 9600
=> 900h = 9600
=>h =  10.67 hours = 10 hr 40 min

Extra time per day
10 hr 40 min − 8 hr
=  2 hr 40 min

Ans (D)

ExpertsGlobal5 · Answer

D is the correct answer choice.

Video explanation:

https://www.youtube.com/watch?v=CFvI1tzzEDg

VibhuAnurag · Answer

Total work: 
 40*60*8 = 19200  
 After 1 month = 30 days, work done =   40*30*8 = 9600  
 So, the remaining work =   19200−9600 = 9600  
 
Now, 30 skilled employees leave. So, remaining skilled employees = 10. 
 They are replaced by 40 new employees who are 50% less productive. 
 --> 40 new employees = 20 skilled employees. 
 Therefore, new team’s effective strength =   10 + 20 = 30  
 
They must complete the remaining work in 30 days. 
 Let required daily hours be h -->   30*30* h = 9600  
 --> h = 96/9 = 10.67 = 10 hours and 40 minutes 
 
 But the question is asking for extra time per day -->   Normal work schedule = 8 hours. 
 --> 10 hours and 40 minutes − 8 hours = 2 hours and 40 minutes

The answer is D.

Flyingdutch1307 · Answer

a super easy trick

40 Emp -> 60d

Now, 30 are replaced with 40, who are 50% efficient. --> in simpler terms, we are getting 20 OG people

so basically we have 30 now, instead of 40

Work done by 40 folks : 30 folks => 4:3 (considering same amount of time)

now, if we want to achieve extra hours, to finish, we need to be 4/3 efficient

So => 8 *4/3 hrs = 10.667 (basicaly 2.667 hrs ~2h40m extra)

40 skilled employees need 60 days to complete a project while working

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40 skilled employees need 60 days to complete a project while working

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