10 men take 30 minutes to wrap 100 articles. How long will it take 40

Question

10 men take 30 minutes to wrap 100 articles. How long will it take 40 men to wrap 200 articles if the new team is half as efficient?

A. 7.5 minutes
B. 15 minutes
C. 30 minutes
D. 60 minutes
E. 120 minutes

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nick1816 · Answer

\frac{E*10*30}{100} =  \frac{E}{2}*\frac{40*T}{200} 
3= \frac{1}{10}*T 
T=30

Archit3110 · Answer

Method 1;

time per article ; 100/30 ; 3.33
time per men ; 3.33/10 ; .33
effici

.33*40 = 13.33
given efficiency is half ; 13.33/2
200*2 /13.3 = 30 
IMO C

Method 2
m1*t1/w1= m2*t2/w2

10*30/100 = 1/2 * 40*t2/200
t2 = 30 mins
IMO C

anupkumar.patel · Answer

we can use the general equation : n*R*t = W
where n - no. of units/ men/ women/ machine etc
R - rate of the work
t - time required for work (note units of time should be consistent)
W - total work completed (usually taken as 1) - in this it is given as 100 & 200

setting up the equation
nRT = W
10R*30 = 100
R = 1/3
So,
40* 1/3 * t = 200
t = 15 min

satya2029 · Answer

40*1/2*(100/300)*t=200
t=30 minutes
C:)

ScottTargetTestPrep · Answer

The rate of 10 men is 100/30 = 10/3, so the rate of 1 man is (10/3)/10 = 10/30 = 1/3. Since the new team of 40 men is only half as efficient, the rate of 1 man in the new team is ⅙, and hence the rate of 40 men is 40/6 = 20/3.

Thus, it takes the new team 200/(20/3) = 600/20 = 30 minutes to wrap 200 articles.

Answer: C

mm229966 · Answer

10 men - 30 minutes - 100 articles - 30/100=3/10 Rate
1 man from the old team - (3/10)/10= 1/3 Rate
1 man from the new team with half the effi. = (1/3)/2 = 1/6
40 men from the new team with new rate = 40/6 = 20/3
The whole new team's timing: 200/(20/3) = 30 minutes - C.

Abhishek009 · Answer

M_1T_1W_2 = M_2T_2W_1

10*30*200 = 40*T_2*100

Or,  T_2 = 15 , Answer must be (B)

Suvanov · Answer

IF THE TEAM IS HALF AS EFFICIENT :/

rajchotu02 · Answer

W1/M1D1=W2/M2D2
So, 100/(10*30)= 200/(40*t)
So, t= 15
But as the new team is half efficient, so t=30 mins (Option C)

Note:   Time is inversely proportional to Efficiency

Regor60 · Answer

When the numbers are simple as these are, should be able to do in your head.

Twice as many articles, twice the time.

But, 4x as many workers, 1/4 the time.

Half as efficient, twice the time.

2*1/4*2 = 1. Same time.

Posted from my mobile device

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10 men take 30 minutes to wrap 100 articles. How long will it take 40

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10 men take 30 minutes to wrap 100 articles. How long will it take 40

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