Last visit was: 25 Nov 2024, 03:10 It is currently 25 Nov 2024, 03:10

Close

GRE Prep 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

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GRE score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 373 [1]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
Intern
Intern
Joined: 15 Jun 2021
Posts: 23
Own Kudos [?]: 12 [1]
Given Kudos: 3
Send PM
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 373 [0]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
Intern
Intern
Joined: 15 Jun 2021
Posts: 23
Own Kudos [?]: 12 [1]
Given Kudos: 3
Send PM
Re: Set A currently has five numbers, and its mean is 918,273,645,321. If [#permalink]
1
motion2020 wrote:
iampratikthorat wrote:
Honestly I cannot explain what I did but I just saw the last 3 digits were different. So I subtracted the two numbers and got 666. Then later just divided that number by 6 coz the addition of new number makes the number of entries 6. I got the answer 111. Now I added 111 to the number which was initially the mean of 5 numbers. And Arrived at option C and to my surprise it turns out to be Correct. So despite solving it please explain what I really should have done and what is the real method for solving such sums ?

Your answer and logic are correct.


Oh, Thanks. Generally I approach most Mean(averages) questions as Sums of Entities. Basically, sum of entities = Mean * number of entities. This formula is quite underrated in my opinion
Manager
Manager
Joined: 23 May 2021
Posts: 146
Own Kudos [?]: 46 [0]
Given Kudos: 23
Send PM
Re: Set A currently has five numbers, and its mean is 918,273,645,321. If [#permalink]
HI , in this method i subtracted both the mean and new entity by 918,273,645 . I got the mean as 321 and the entity as 987 . I then multiplied 321 * 5 and got the answer as 1605 and added 987 to it and then divided by 6 and got the answer as 432 which is the last digit of option C .

Is my method correct?
Retired Moderator
Joined: 02 Dec 2020
Posts: 1831
Own Kudos [?]: 2146 [1]
Given Kudos: 140
GRE 1: Q168 V157

GRE 2: Q167 V161
Send PM
Set A currently has five numbers, and its mean is 918,273,645,321. If [#permalink]
1
Yes that can be done as well.

Similarly,

As this is a large no, take the last two \(21\) as the mean of five nos, so total will be \(105\).

Now new no \(987\), but take last two \(87\) and add them to \(105\), so the sum will be \(192\).

When divided by \(6\), the answer will be \(32\). Last two digits of the correct answer.


aishumurali wrote:
HI , in this method i subtracted both the mean and new entity by 918,273,645 . I got the mean as 321 and the entity as 987 . I then multiplied 321 * 5 and got the answer as 1605 and added 987 to it and then divided by 6 and got the answer as 432 which is the last digit of option C .

Is my method correct?


Posted from my mobile device
Prep Club for GRE Bot
Set A currently has five numbers, and its mean is 918,273,645,321. If [#permalink]
Moderators:
GRE Instructor
84 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne