Two secretaries, Sally and Lisa, type at even but difference paces. Sa

Question

Two secretaries, Sally and Lisa, type at even but difference paces. Sally is more experienced and types 80 characters per minute. Lisa, a beginner, can type only 30 characters per minute. On one day, Lisa starts typing before Sally. At some point, both have typed the same number of characters. Then both continue typing and Sally types 800 more more than what? characters until her computer breaks down. Assuming Lisa does not take any break, how long, in hours, will it take her to finish typing the same number same number as what? of characters?

A. 53/180

B. 4/9

C. 13/18

D. 15/23

E. 5/18

Source: Manhattan Review

A. 53/180
 
B. 4/9
 
C. 13/18
 
D. 15/23
 
E. 5/18

Source:  Manhattan Review

IanStewart · Answer

This question is truly incomprehensible. I can't even guess what it's trying to say, at least if these are the answer choices. I've pointed out two of the problems with the wording, but no matter what plausible interpretation I try to make of those phrases, none of the answers is even close to being correct (edit - I wasn't reading carefully enough, because the question didn't make enough sense to be worth thinking about, so I missed the units conversion to hours, but depending how you interpret the wording, you could justify either 4/9 or 5/18 as the answer).

MBBDorBust · Answer

The answer is B. The fact they're typing before the point at which they had typed an equal number of characters is irrelevant.

"800 more" means "800 additional". More is not necessarily a comparison.
"The same number" refers to number of characters Sally typed, which is 800 + x, where x is what they typed at the point they had typed the same number of characters. Since we know Lisa also typed x characters previously, the question is really asking

"Lisa types 30 characters per minute. How long does it take her to type 800 characters?"
The answer is 800 / 30 * 1/60 = 800/1800 = 4/9

I don't see any other reasonable interpretation of the question. Even if you interpret "the same number" as being "800" rather than "800 + x", you'll get the same answer.

Bunuel · Answer

_________________
The OA given is E.

CrackverbalGMAT · Answer

Key word here is " how long will it take to   finish   typing 800 characters". This takes into account that Lisa has already typed some words and the question asks how much time it would take to type the remainder of characters as typed by Sally.

The first part is not required. we take it from the point, where both have typed equal number of characters.

Now, If sally has typed 800 characters @ 80 characters/minute, then time taken =  \frac{800}{80}= 10  minutes

In 10 minutes, the number of characters typed by Lisa ( 30  characters/minute) = 10 * 30 = 300 characters

Time it takes for her to type the remaining 800 - 300 = 500 characters =  \frac{500}{30} = \frac{50}{3}  minutes

To convert minutes to hours, we divide by 60 =  \frac{\frac{50}{3}}{60} = \frac{50}{180} = \frac{5}{18}

Option E

Arun Kumar

MBBDorBust · Answer

Ahh, I'm embarrassed and didn't read the question carefully. It's how long will it take her to  finish  typing.

So it should be (800/30 - 800/80)/60 = 5/18

Two secretaries, Sally and Lisa, type at even but difference paces. Sa

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