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If 20 typists can type 48 letters in 20 minutes, then how many letters
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09 Jun 2016, 02:27
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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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09 Jun 2016, 02:55
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 Typistletterstime204820 2048*320*3 1\(\frac{48*3}{20}\)60 min 30\(\frac{48*3*30}{20}\)60 min Answer = \(\frac{48*3*30}{20}=24*3*3 = 216\) D
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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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09 Jun 2016, 02:49
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 It is always better to find out the time needed for typing one letter in such problems. Total typist minutes required to type 48 letters = 20*20 = 400 minutes. Time needed for each letter = 48/400 minutes. Number of letters completed by 30 typists in 60 minutes = (48/400) * 30*60 = 216 letters. Correct Option: D



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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09 Jun 2016, 09:44
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 20 typists can type 48 letters, so 30 typists can type = 48*30/20 48*30/20 letters can be typed in 20 mins. In 60 mins typist can type= 48*30*60/20*20= 216 D is the answer
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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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09 Jun 2016, 09:48
simple formula of mandays
(20*20)/(60*48) = (30*1)/x
x = 216



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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09 Jun 2016, 12:12
20 typist type 48 letters, so 30 typists type = (48/20) * 30 letters in 20 mins.
in 60 mins 30 typists type, = (48/20*20) * 30 * 60 = 216
answer D



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If 20 typists can type 48 letters in 20 minutes, then how many letters
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14 Jun 2016, 22:27
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 We have given Man ( typists) , Days , Hours ( time ) and Work ( letters ) and two different MAN DAY cases Then apply simple formula and very important. M1 D1 H1 / W1 = M2 D2 H2 / W2. ( Ignore days as this is not mentioned in Question ). Let the unknown work i.e. no of letters be X and 1 hour = 60 mins. 20 * 20 / 48 = 30 * 60 / X. X = 216. Option D.



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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15 Jun 2016, 00:36
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 20 typists can type 48*20 letter minutes 20*20 typistminutes is equal to 48 letters 1 typistminute is equal to 48/(20*20) letters 30*60 typistminutes is equal to 48*30*60/(20*20) letters =216 letters.



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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03 Jul 2016, 10:22
The question is asking about the amount of work done in 60 mins or 1 hours. Using this information we can calculate, the amount of work done by 20 typists in 60 minutes 3 (20)*48 = 144 words. Now we can use the unitary method to find the work done by 30 typists in 60 mins i.e. 144/20*30 = 216 word.
Tip: For a fixed time more men imply more work. (considering work done by each man is consistent) therefore, we can also eliminate answer choice A, B, C.



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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03 Jul 2016, 10:51
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 20 typists can type 48 letters in 20 minutes So, working at same pace 20 typists can type 48*3 letters in 1 hour (20*3 minutes) Or, 20 typists can type 144 letters/hr So, Efficiency per worker is 144/20 If 30 workers are employed , they can produce = 144/20*30 =>216 letters Answer will be (D)
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If 20 typists can type 48 letters in 20 minutes, then how many letters
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03 Jul 2016, 19:37
48/(20*1/3)=36/5=rate of one typist in one hour 30*36/5=216 letters in one hour



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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10 Jan 2017, 10:06
I used ratios typers:letters:mins 20:48:20 Question asks for one hour first converted 20 mins into one hour by multiplying by 3 Letter:mins 48(3):20(3) 144:60 mins
then to make the 20 equal to 30 typers i multiplied by 3/2 and also multiplyed 3/2(144) typers : letters 20(3/2) = 30 typers : 144(3/2) = 216 letters 30 typers: 216 letters



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If 20 typists can type 48 letters in 20 minutes, then how many letters
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03 Jun 2017, 13:37
20 machines times their constant respective rate in 20 minutes can produce 48 letters. Therefore, \(20*(r) * 20 = 48,\) Rate\((r)=\frac{48}{20} * \frac{1}{20} => r= \frac{48}{400}\)
30 machines in 1 hour (60 minutes) will produce how many letters:
\(30 * \frac{48}{400} * 60 = 3*\frac{48}{4}*6 = 18*12=216\)
Option: D



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Re: If 20 typists can type 48 letters in 20 minutes, then how many letters
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01 Aug 2018, 16:27
Bunuel wrote: If 20 typists can type 48 letters in 20 minutes, then how many letters will 30 typists working at the same rate complete in 1 hour?
A. 63 B. 72 C. 144 D. 216 E. 400 We can set up a proportion to determine the rate n (number of letters per minute) of 30 typists. 20 typists / rate of those 20 typists = 30 typists / (unknown) rate of those 30 typists 20/(48/20) = 30/n 20/(12/5) = 30/n 100/12 = 30/n 100n = 12 x 30 10n = 12 x 3 10n = 36 n = 3.6 We see that the rate of 30 typists is 3.6 letters per minute. So in 60 minutes, 30 typists can complete 3.6 x 60 = 216 letters. Alternate Solution: We know that 20 typists can type 48 letters in 20 minutes. Thus, we see that in 60 minutes, or 1 hour, those 20 typists can type 3 times as many letters, or 3 x 48 = 144 letters. We can now set up a proportion for n = the number of letters that can be typed in 1 hour by 30 typists: 20/144 = 30/n 20n = 144 x 30 2n = 144 x 3 n = 216 Answer: D
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