Last visit was: 22 Dec 2024, 19:30 It is currently 22 Dec 2024, 19:30

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
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36822 [6]
Given Kudos: 26100
Send PM
avatar
Director
Director
Joined: 03 Sep 2017
Posts: 518
Own Kudos [?]: 707 [0]
Given Kudos: 0
Send PM
avatar
Intern
Intern
Joined: 17 Feb 2018
Posts: 31
Own Kudos [?]: 42 [2]
Given Kudos: 0
Send PM
avatar
Intern
Intern
Joined: 14 Apr 2018
Posts: 7
Own Kudos [?]: 15 [3]
Given Kudos: 0
Send PM
Re: How many three-digit integers can be created from 5 distinc [#permalink]
2
1
Bookmarks
hugebigmac wrote:
you can also use 5P3 instead 5C3 in order to get the answer faster. 5P3=5X4X3=60

This question seems troublesome for me. What if 0 is included in the 5 distinct given digits?
Assuming that 0 is not included in the 5 given digits, I think that 5*5*5=125 should be the answer instead of 60 since integers with 3 similar digits must also be included.
Please let me know your thought!
avatar
Intern
Intern
Joined: 03 Mar 2015
Posts: 14
Own Kudos [?]: 21 [1]
Given Kudos: 0
Send PM
How many three-digit integers can be created from 5 distinc [#permalink]
1
halam wrote:
hugebigmac wrote:
you can also use 5P3 instead 5C3 in order to get the answer faster. 5P3=5X4X3=60

This question seems troublesome for me. What if 0 is included in the 5 distinct given digits?
Assuming that 0 is not included in the 5 given digits, I think that 5*5*5=125 should be the answer instead of 60 since integers with 3 similar digits must also be included.
Please let me know your thought!


Carcass,

Kindly have a re-look at this question! Seems to be a poorly framed one!

Originally posted by askhere on 19 Apr 2018, 17:59.
Last edited by askhere on 17 Nov 2021, 16:30, edited 1 time in total.
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36822 [0]
Given Kudos: 26100
Send PM
Re: How many three-digit integers can be created from 5 distinc [#permalink]
Expert Reply
what do you mean ??

Regards
avatar
Intern
Intern
Joined: 03 Mar 2015
Posts: 14
Own Kudos [?]: 21 [4]
Given Kudos: 0
Send PM
How many three-digit integers can be created from 5 distinc [#permalink]
4
Carcass wrote:
what do you mean ??

Regards


Two things:

All the answers here assume digits cannot be repeated. Why? Does the question mention so?

The question states: "How many three-digit integers can be created from 5 distinct digits?"

If we assume five distinct digits to be {1,2,3,4,5}

Can't I create three digit integer "111" form the above set of numbers?

Per the question, 111 is a three-digit integer that "can be created" from the given set of numbers
Per the question, 112 is another three-digit integer that "can be created" from the given set of numbers.

And so on and so forth...

Maybe the author meant to say "How many 3 digit integers with distinct digits can be created from 5 distinct digits?"

So, if we assume 1,2,3,4,5 to be the 5 digits we get following 60 three digit integers with "distinct digits"

123 124 125 134 135 145 234 235 245 345
132 142 152 143 153 154 243 253 254 354
213 214 215 314 315 415 324 325 425 435
231 241 251 341 351 451 342 352 452 453
312 412 512 413 513 514 423 523 524 534
321 421 521 431 531 541 432 532 542 543

These could be the combinations that the author might have visualized. But to get these, question should have been modified to ensure digits are not repeated!!

But the problem does not end here!!!

What if "0" is a digit out of the 5 distinct digits?? For example: {0,1,2,3,4}

Here I cannot have 012, 013 etc. as three digit integers. So the number of possibilities will reduce further!

Isn't the question ambiguous?

Originally posted by askhere on 21 Apr 2018, 07:35.
Last edited by askhere on 17 Nov 2021, 16:30, edited 1 time in total.
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36822 [0]
Given Kudos: 26100
Send PM
Re: How many three-digit integers can be created from 5 distinc [#permalink]
1
Expert Reply
Yes, you are right.

the problem is one: it comes from a NON-official source. This is a good chance to learn that official material is the only one-stop solution resource in the last stage of your preparation for the exam. The rest is good to practice.

Regards
avatar
Intern
Intern
Joined: 03 Mar 2015
Posts: 14
Own Kudos [?]: 21 [0]
Given Kudos: 0
Send PM
How many three-digit integers can be created from 5 distinc [#permalink]
Thanks to halam for pointing this out.

Carcass, maybe this question should be marked as "Poor question" so that other students don't get confused!

Originally posted by askhere on 21 Apr 2018, 08:33.
Last edited by askhere on 17 Nov 2021, 16:31, edited 1 time in total.
Verbal Expert
Joined: 18 Apr 2015
Posts: 30475
Own Kudos [?]: 36822 [0]
Given Kudos: 26100
Send PM
Re: How many three-digit integers can be created from 5 distinc [#permalink]
Expert Reply
Well, after all, it is from Princeton. A really well-established prep company.

If we do start to label which one is poor or bad or else we will end up to study with only the Official material.

Instead, think this way: what do we learn from a question like this, with the help of the guys here on the board ?? to spot where is a possible pitfall.

This is useful to improve our skills and see a question "behind the lines". Therefore, there is something positive from which we can have benefit.

Regards
avatar
Intern
Intern
Joined: 27 Nov 2014
Posts: 30
Own Kudos [?]: 8 [0]
Given Kudos: 0
Send PM
Re: How many three-digit integers can be created from 5 distinc [#permalink]
It's permutation math. 5P3 = 60. So, the answer is E
User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 5090
Own Kudos [?]: 76 [0]
Given Kudos: 0
Send PM
Re: How many three-digit integers can be created from 5 distinc [#permalink]
Hello from the GRE Prep Club BumpBot!

Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Prep Club for GRE Bot
Re: How many three-digit integers can be created from 5 distinc [#permalink]
Moderators:
GRE Instructor
88 posts
GRE Forum Moderator
37 posts
Moderator
1115 posts
GRE Instructor
234 posts

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