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# Typists problem Go to solution Solved by unreality,

## Question If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

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two

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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

2 ?

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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

If two typists can type two pages in two minutes, then one typist can type one page in one minute, which means she can then types a page/minute and would be able then to type 18 pages in 18 minutes since it's still a 1:1 ratio.

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If two typists can type two pages in two minutes,

then one typist can type one page in one minute,

Two typists [together] can type at a pace of 1 page/minute.

and therefore, also, they can type 18 pages in 18 minutes

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• 0 If two typists can type two pages in two minutes,

then one typist can type one page in one minute,

Two typists [together] can type at a pace of 1 page/minute.

and therefore, also, they can type 18 pages in 18 minutes

very true, thanks. I just thought 2 was such an obvious answer, so I tried to search further for something else, but... I can't argue with the correct math. 2 typist together type 1ppm so apart, assuming each is equal, each types .5ppm. Indeed both of them would be needed for the speed of 1ppm to type 18 pages in 18 minutes.

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I first heard it posed as ... if a hen and a half can lay an egg and a half in a day and a half, how many hens would it take to lay 18 eggs in 3 days?

It's tempting to figure a hen can lay an egg a day so it would take 6 hens. But it takes a hen and a half to lay an egg a day, so it takes 9 .

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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

9 minutes

If it takes 2 typists, 2 mintues to type 2 pages, then they type 1 page each in 2 minutes. 18/2=9

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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

The answer is the one and only one.

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• 0 well, this really isn't solvable without making some assumptions. Assuming all typists are the same then the answer is 1. Now if these 2 unique typist type together and we want to make sure they're done in 18 mintues exactly, then it will take 2. Typist A could be faster than typist B but they average 1/page per minute together.

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• 0 Oone typist!

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• 0 It will take two typists.

Each typist is only typing 1/2 page per minute. (1 typist x 1/2 page per minute) x 2 minutes will yield 1 page; so to get two pages in two minutes, you need two typists.

Therefore at only 1/2 page per minute, it would take 36 minutes for one typist to finish 18 pages.

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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

Assumption: all typists are the same.

Now:

Can each typist type two pages in two minutes? If so, the answer is one, because each typist types one page per minute.

Or, do the two typists type, in total, two pages in two minutes? Then the answer is 2 because every two typists types one page per minute.

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• 0 I know it seems like the answer should be one, but if each typist can type a page a minute, and you have two typists, then after two minutes you would have 4 pages.

So the answer must be 2.

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• 0 Um.......9? cause 2=2 min 2 times 9 is 18 so.....ya  i hope its right.....

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• 0 I first heard it posed as ... if a hen and a half can lay an egg and a half in a day and a half, how many hens would it take to lay 18 eggs in 3 days?

It's tempting to figure a hen can lay an egg a day so it would take 6 hens. But it takes a hen and a half to lay an egg a day, so it takes 9 .

In general to solve problems of this type, one can proceed as follows:

Prepare a data table

^ hens eggs days

| 1.5.... 1.5 ....1.5

| x .......18...... 3

Draw an arrow from the unknown x to the known value (in this case of hens). The value of x is then obtained by multiplying the known value by the ratios of the other quantities taken in the same direction of the arrow if they are directly proportional with respect to the unknown x, in the opposite direction if inversely porportional. In this case the number of eggs is directly proportional (more hens, more eggs), the days are inversely proportional (more days, less hens necessary to lay a certain number of eggs).

x = 1.5x(18/1.5)x(1.5/3) = 9.

For the typists problem we have:

^ typists pages minutes

| 2...........2...........2

| x...........18........18

In this case the pages are directly proportional (more typists, more pages), the minutes inversely proportional (more typists, less time to type a certain number of pages). So:

x = 2x(18/2)x(2/18) = 2.

(I couldn't find a better method of drawing the arrow)

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• 0 Two typists type two pages in two minutes so 1 typist types 1 page in 2 minutes. So in 18 minutes 1 typist can type 9 pages. So the answer is 2 typists can type 18 pages in 18 minutes.

Edited by Ghan3sh
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• 0 "If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?"

This question is flawed due to ambiguity. It is missing a word and thus causing confusion. For example:

"If two typists can EACH type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?" typing rate per typist is 1 page per minute

"If two typists TOGETHERcan type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?" typing rate per typist is 1/2 page per minute

I believe the question as posed can be reasonably understood as having both meanings, thus clarification is required.

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• 0 nine?

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• 0 assuming each of the first 2 typist each type a page per minute, and not one type 1 and a 1/2 and the other type 1/2. you only need one of them for 18 pages in 18 minutes

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• 0 if 2 typists type 2 pages in 2 minutes, then 1 will type 1 page in 2 mins. It will therefore take 1 typist 36 mins to type 18 pages, and therefore it will take 2 typists 18 mins to type 18 pages.

Unless there is a trick in the wording, and 2 typists type 2 pages each in 2 minutes, then 1 will type 1 page in 1 minute, and 1 will type 18 pages in 18 minutes.

Edited by munkifisht
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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

Actually, I don't think there is enough information to solve to problem. We need to know how many typewriters are present.

If there is only one typewriter, then each typist typed 1 page in 1 minute. Therefore a single typist could do 18 pages in 18 minutes.

However, if there were 2 typewriters available, then it took each typist 2 minutes to type 1 page each. It would be impossible for any number of such typists to type 18 pages in 18 minutes.

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• 0 Actually, I don't think there is enough information to solve to problem. We need to know how many typewriters are present.

If there is only one typewriter, then each typist typed 1 page in 1 minute. Therefore a single typist could do 18 pages in 18 minutes.

However, if there were 2 typewriters available, then it took each typist 2 minutes to type 1 page each. It would be impossible for any number of such typists to type 18 pages in 18 minutes.

It really doesent matter. two typists in two minutes= 1 typist in 1 minute. therefore the only possible answer is one, because only one typist could type 18 pages in 18 minutes.

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• 0 If two typists can type two pages in two minutes, how many typists does it take to type 18 pages in 18 minutes?

2 typist.2 can write 2 pages for 2 min,i.e. 2 typist write with the speed of 1 page/min,i.e. 2 typist will write 18 pages for 18 min.

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