Events & Promotions
|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2601:30 AM EDT
-02:30 AM EDT
Learn how Keshav, a Chartered Accountant, scored an impressive 705 on GMAT in just 30 days with GMATWhiz's expert guidance. In this video, he shares preparation tips and strategies that worked for him, including the mock, time management, and more.
Apr 2512:30 AM EDT
-01:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
May 0111:00 AM PDT
-12:00 PM PDT
Free- full-length test + 15 concept videos + 150+ short videos + study plan!
01 Mar 2019, 15:52
Kudos
Bookmarks
D
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
25%
(medium)
Question Stats:
81% (01:50) correct
19%
(02:08)
wrong
based on 736
sessions
History
Date
Time
Result
Not Attempted Yet
Five batches of 100 nails each are taken from a production line. The numbers of defective nails in the first four batches are 2, 4, 3, and 5, respectively. If the fifth batch has either 1, 2, or 6 defective nails, for which of these values does the average (arithmetic mean) number of defective nails per batch for the five batches equal the median number of defective nails for the five batches?
I. 1
II. 2
III. 6
A. I only
B. II only
C. III only
D. I and III only
E. I, II, and III
I. 1
II. 2
III. 6
A. I only
B. II only
C. III only
D. I and III only
E. I, II, and III
Updated on: 02 Mar 2019, 09:19
Originally posted by Henry S. Hudson Jr. on 01 Mar 2019, 19:03.
Last edited by Henry S. Hudson Jr. on 02 Mar 2019, 09:19, edited 1 time in total.
Last edited by Henry S. Hudson Jr. on 02 Mar 2019, 09:19, edited 1 time in total.
Kudos
Bookmarks
Consider the cases.
The first four batches have a total of 2+3+4+5=14 defective nails.
If the fifth batch has 1 defective nail, then the total number of defective nails is 14+1=15. The average is 15/5=3
If we order them (1,2,3,4,5) we see the median IS 3. Since the mean and median are both 3, having 1 defective nail in the fifth batch
satisfies the condition.
If the fifth batch has 2 defective nails, the average would be 16/5=3.2
If we order them (2,2,3,4,5) we see the median is 3. The median doesn't equal the mean in this case.
If the fifth batch has 6 defective nails, the total would be 14+6=20. The average would be 20/5=4
In order (2,3,4,5,6) we see the median is 4. The mean DOES equal the median.
Having 1 or 6 nails in the fifth batch satisfies the condition.
The first four batches have a total of 2+3+4+5=14 defective nails.
If the fifth batch has 1 defective nail, then the total number of defective nails is 14+1=15. The average is 15/5=3
If we order them (1,2,3,4,5) we see the median IS 3. Since the mean and median are both 3, having 1 defective nail in the fifth batch
satisfies the condition.
If the fifth batch has 2 defective nails, the average would be 16/5=3.2
If we order them (2,2,3,4,5) we see the median is 3. The median doesn't equal the mean in this case.
If the fifth batch has 6 defective nails, the total would be 14+6=20. The average would be 20/5=4
In order (2,3,4,5,6) we see the median is 4. The mean DOES equal the median.
Having 1 or 6 nails in the fifth batch satisfies the condition.
01 Mar 2019, 23:45
Kudos
Bookmarks
In any 'equally spaced' list of numbers, the mean and median are always equal. So in this list, say:
1, 2, 3, 4, 5
(where the list increases by 1 each time), or in this list:
10, 17, 24, 31, 38, 45, 52
(where the list increases by 7 each time), the mean and the median are definitely equal.
If you know that, you can instantly see in this question that 1, 2, 3, 4, 5 and 2, 3, 4, 5, 6 will both be lists with equal mean and median. And since 2, 2, 3, 4, 5 has the same median as, but a larger mean than 1, 2, 3, 4, 5, then it can't be true that the mean and median are the same for this list. So the answer is I and III only.
1, 2, 3, 4, 5
(where the list increases by 1 each time), or in this list:
10, 17, 24, 31, 38, 45, 52
(where the list increases by 7 each time), the mean and the median are definitely equal.
If you know that, you can instantly see in this question that 1, 2, 3, 4, 5 and 2, 3, 4, 5, 6 will both be lists with equal mean and median. And since 2, 2, 3, 4, 5 has the same median as, but a larger mean than 1, 2, 3, 4, 5, then it can't be true that the mean and median are the same for this list. So the answer is I and III only.
