Two typists P and Q work individually for 6 hours a day. What is the

Question

Two typists P and Q work individually for 6 hours a day. What is the difference between the average number of pages typed per hour by person P on a single day and the average number of pages typed per hour by person Q on the single day?

(1) The typing speed of the person P is constant and is 10 pages per hour, whereas the typing speed of person Q is 19 pages per hour for initial three hours on the same day.

(2) Twice the average number of pages typed by person Q in one hour is 3.8 times the average number of pages typed by person P in one hour.

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ManifestDreamMBA · Answer

Let daily avg speed for each typist be P and Q
Hours worked daily = 6hr

Statement 1
P = 10
Q = 19 for initial three hours
However, we don't know the avg speed for Q for the last 3 hours
Insufficient

Statement 2
2Q = 3.8P
Q = 1.9P

Difference = Q-P = 1.9P - P = 0.9P
However, we don't know the value of P

Combined, we have the value of P= 10, so the difference between the average number of pages typed per hour is 9 pages/hour

Sketchitesh · Answer

Q : | Pavg - Qavg | =

1. Pavg = 10 , Q(Avg for 3 hours)= 19. no info on remaining 3 hours of Q.  Insufficient. 
 
2. 2 Qavg = 3.8 Pavg => Qavg = 1.9 Pavg => | Pavg - Qavg | = | 0.9 Pavg | .. No value of Pavg or Qavg given.  Insufficient.

Combined, taking Pavg =10 (Statement 1)

| Pavg - Qavg | = | 0.9 Pavg | = | -9 | = 9 Sufficient.  C is correct

Note : I have doubts on language of statement two. it said average no of pages in one hour 
while Argument had Average number of pages per hour in single day. So I am little skeptical. Waiting fir OA.

bhargavhhhhhhhh · Answer

We are asked: 
What is the difference between the **average pages per hour** typed by P and Q in one day (6 hours)?

Let’s denote: 
P_avg = average pages per hour typed by P 
Q_avg = average pages per hour typed by Q 
We want to find: |P_avg − Q_avg|

Statement (1): 
P types at a constant rate of 10 pages/hour 
Q types at 19 pages/hour for first 3 hours; rest is unknown 
→ Not enough info about Q’s speed in last 3 hours → Cannot find Q_avg → Insufficient

Statement (2): 
2 × Q_avg = 3.8 × P_avg 
→ Gives us a ratio: Q_avg / P_avg = 1.9 
So Q_avg = 1.9 × P_avg 
But we still don’t know the exact value of either P_avg or Q_avg → Cannot find actual difference → Insufficient

Combining (1) and (2): 
From (1): P_avg = 10 
From (2): Q_avg = 1.9 × P_avg = 1.9 × 10 = 19 
→ Difference = 19 − 10 = 9

Now we can compute the exact difference.

Statements together → Sufficient

Answer: C

Dereno · Answer

The two typists P and Q work individually for 6 hours a day.

Let the average pages typed by each typist in a single day of 6 hrs work is  Pa  and  Qa  respectively .

To find : Difference of (Pa - Qa).

Statement 1:

(1) The typing speed of the person P is constant and is 10 pages per hour, whereas the typing speed of person Q is 19 pages per hour for initial three hours on the same day.

Given, typing speed of P is 10 pages /hr . Then for 6 hrs it’s 60 pages. Pa = 10 pages/hr.

Q is typing 19 pages per hour - for the initial 3 hrs of the day.

What about the next 3 hrs?? Is the pages typed > 19 or <19?

No information about the remaining 3 hours. Hence,  NOT SUFFICIENT.

Statement 2:

(2) Twice the average number of pages typed by person Q in one hour is 3.8 times the average number of pages typed by person P in one hour.

Given 2* Qa = 3.8 * Pa

thus, Qa / Pa = 19/10.

Ratio is not sufficient to determine the true values of Qa and Pa. Hence,  NOT SUFFICIENT.

Combining statements 1 and 2,  we come to know the value of Pa =10, which gives the value of Qa =19.

Hence, Qa - Pa = 19 - 10 = 9.  Option C

Abhiswarup · Answer

Difference between avg no. pages/hr for P & Q is required

Avg pages/hr for P= X
Avg pages/hr for P= Y

Statement 1

P has constant rate= 10 pages/hr which is its avg.

Q has rate of 19 pages/hr for initial 3 hours, rest 3 hurs nothing can be arrived from statement.

Thus statement 1 is not sufficient.

Statement 2
2Y=3.8 X
Statement 2 is not sufficient

Combining both we get X= 10 & Y = 19

difference= 9 pages/hr
Answer is C.

NextstopISB · Answer

Question:
Two typists P and Q work individually for 6 hours a day. What is the difference between the average number of pages typed per hour by person P on a single day and the average number of pages typed per hour by person Q on the single day?

(1) The typing speed of the person P is constant and is 10 pages per hour, whereas the typing speed of person Q is 19 pages per hour for initial three hours on the same day.

(2) Twice the average number of pages typed by person Q in one hour is 3.8 times the average number of pages typed by person P in one hour.

P types 10 pages per hour constantly → In 6 hours, P types:
10 × 6 = 60 pages → So, P's average = 60 / 6 = 10 pages/hour.

Q types 19 pages/hour for the first 3 hours, but nothing is mentioned about the last 3 hours.

So we cannot calculate Q’s total or average typing speed.

→ Statement (1) alone is Not Sufficient.

We are told:

2 × (Q’s avg) = 3.8 × (P’s avg) 
=> (Q’s avg)/(P’s avg) = 3.8 / 2 = 1.9

This gives only the ratio between Q and P’s averages, not their actual values.

So we cannot compute the exact difference between their averages.

→ Statement (2) alone is Not Sufficient.

From Statement (1): P’s average = 10 pages/hour 
From Statement (2): Q = 1.9 × P = 1.9 × 10 = 19 pages/hour

So the difference = 19 - 10 = 9 pages/hour

→ Both statements together are Sufficient

Answer: (C) – Both statements together are sufficient, but neither alone is sufficient.

Two typists P and Q work individually for 6 hours a day. What is the

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GMAT Data Sufficiency (DS) Questions

Two typists P and Q work individually for 6 hours a day. What is the

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