Last visit was: 21 Apr 2026, 03:57 It is currently 21 Apr 2026, 03:57
Close
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

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 GMAT 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
User avatar
jai169
Joined: 25 May 2024
Last visit: 22 Mar 2026
Posts: 10
Own Kudos:
Given Kudos: 3
Posts: 10
Kudos: 7
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
msignatius
Joined: 28 Aug 2025
Last visit: 09 Apr 2026
Posts: 131
Own Kudos:
98
 [1]
Given Kudos: 31
Location: India
Concentration: Strategy, Marketing
GMAT Focus 1: 705 Q86 V85 DI84
GPA: 3.5
WE:Marketing (Consulting)
Products:
GMAT Focus 1: 705 Q86 V85 DI84
Posts: 131
Kudos: 98
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
asperioresfacere
Joined: 03 Nov 2025
Last visit: 21 Apr 2026
Posts: 61
Own Kudos:
53
 [2]
Given Kudos: 106
Posts: 61
Kudos: 53
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
tanvi0915
Joined: 01 Oct 2025
Last visit: 19 Apr 2026
Posts: 30
Own Kudos:
21
 [1]
Given Kudos: 6
Posts: 30
Kudos: 21
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The question is checking for the number of distinct remainders we can have when prime greater than 10 is divided by 18. We know all remainders will be less than 18 i.e 0 to 17 and since 2 & 3 are factors of 18 so the remainder should not be divisible by 2 or 3 otherwise the original number will not be a prime. Therefore the distinct remainder would be 1,5,7,11,13,17 .

Answer is D 6
User avatar
Vaidehii
Joined: 15 Apr 2025
Last visit: 21 Mar 2026
Posts: 5
Own Kudos:
4
 [1]
Posts: 5
Kudos: 4
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Solution: It is written that positive integers greater than 10 that have no factor p such that 1<p< the number so the number is prime factor.

Also the prime numbers greater than 10 are:

11,13,17,..

->When any number is divided by 18 then the remainder must be one of:
0,1,2,..17

Also numbers are prime and greater than 10

we can eliminate 0,6,12(because 18 is even and they are not divisible by 2 or 3 so the remainder cannot be 0,6, or 12 or we can say multiples of 6)

->Hence remaining possible remainders are 1,5,7,11,13,17
25 is not prime and also 35 is not prime
23/18=5 19/18=1 29/18=11 31/18=13 37/18=1 53/18=17 57/18=11 43/18=7

So all six remainders do occur hence ans is 6
User avatar
Lizaza
Joined: 16 Jan 2021
Last visit: 29 Mar 2026
Posts: 240
Own Kudos:
282
 [1]
Given Kudos: 7
GMAT 1: 710 Q47 V40
GMAT 1: 710 Q47 V40
Posts: 240
Kudos: 282
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Since the generated integers have no factors except for themselves and 1, they must be prime numbers. Then, the question is - what possible remainders from dividing by 18 they can have?

Let's start counting from any number that is actually divisible by 18. All numbers that are also divisible by 3 won't be prime, so we can exclude remainders 3 / 6 / 9 / 12 / 15 (since with such remainders the numbers will preserve divisibility by 3 from 18).
Also, since 18 is even, we can exclude all even remainders from our prime number list, meaning excluding 2 / 4 / 6 / 8 / 10 / 12 / 14 / 16.

As a result, we're only left with the following six possible remainders: 1 / 5 / 7 / 11 / 13 / 17. And just to check, we can find examples of prime numbers for each of them, such as 19(1), 23(5), 43(7), 29(11), 31(13) and 43(17).

Therefore, the answer is D.
User avatar
dp1234
Joined: 15 Nov 2021
Last visit: 20 Apr 2026
Posts: 93
Own Kudos:
66
 [1]
Given Kudos: 166
Products:
Posts: 93
Kudos: 66
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
A computer program randomly generates positive integers greater than 10 that have no factor p such that 1 < p < the generated number. Each time a number is generated, the program divides it by 18 and records the remainder. How many distinct remainders could the program possibly record?

A. 3
B. 4
C. 5
D. 6
E. 9

Gift
12 Days of Christmas Competition
This question is part of our holiday event
Win $40,000 in prizes: courses, tests, and more

A number N having no factor for range (1,N) means only N and 1 are its factors i.e. it's a prime number. So list prime number above 18 (since we are trying to find remainders only), -> 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 71, 73, 79, 83, 89, 97. And find the remainders - we will observe that unique remainders are 1, 5, 7, 11, 13, 17. Total - 6
User avatar
Mardee
Joined: 22 Nov 2022
Last visit: 02 Feb 2026
Posts: 225
Own Kudos:
191
 [1]
Given Kudos: 20
Posts: 225
Kudos: 191
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Considering the fact the program generates positive integers greater than 10 that have no factor p such that 1 < p < the number, it basically implies they are a prime number
And these prime numbers are greater than 10 as given

Now each of these numbers are divided by 18 and their remainder is recorded and we need to know distinct remainders possible
Now these remainders should also be relatively prime to 18

Thus the possible remainders should be between 0 and 17 and shouldnt be divisble by 2 or 3

=> Distinct Remainders possible = {1,5,7,11,13,17}

D. 6
User avatar
crimson_king
Joined: 21 Dec 2023
Last visit: 21 Apr 2026
Posts: 152
Own Kudos:
156
 [1]
Given Kudos: 113
GRE 1: Q170 V170
GRE 1: Q170 V170
Posts: 152
Kudos: 156
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
It is given that the program generates prime numbers greater than 10.

Since , any prime number greater than 3:

is not divisible by 2 & not divisible by 3


So the remainder when dividing by 18 cannot be even or a multiple of 3.

Possible remainders from 0 to 17 that are not divisible by 2 or 3 are:

1, 5, 7, 11, 13, 17

There are 6 such remainders.

Therefore the answer is option D
User avatar
sanjitscorps18
Joined: 26 Jan 2019
Last visit: 03 Mar 2026
Posts: 723
Own Kudos:
739
 [1]
Given Kudos: 130
Location: India
Schools: IMD'26
Products:
Schools: IMD'26
Posts: 723
Kudos: 739
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
No factor p between 1< p < generated number. Hence a prime number.

Writing prime numbers after 10 we get

11 Mod 18 = 11
13 Mod 18 = 13
17 Mod 18 = 17
19 Mod 18 = 1
23 Mod 18 = 5
29 Mod 18 = 11
31 Mod 18 = 13
37 Mod 18 = 1
41 Mod 18 = 5
43 Mod 18 = 7
47 Mod 18 = 11

These are all odd remainders, and we can say that if there is an even remainder after dividing by 18, it would be an even integer (greater than 10) and would not be a prime number.

Remaining remainders = 3, 9, 15. Let's take the numbers individually

a) 3, any number of the form 18x + 3 would always be divisible by 3
b) 9, any number of the form 18x + 9 would always be divisible by 9 and 3
c) 15, any number of the form 18x + 15 would always be divisible by 3

Hence the possible remainders would be 1, 5, 7, 11, 13, 17

Option D

Bunuel
A computer program randomly generates positive integers greater than 10 that have no factor p such that 1 < p < the generated number. Each time a number is generated, the program divides it by 18 and records the remainder. How many distinct remainders could the program possibly record?

A. 3
B. 4
C. 5
D. 6
E. 9

Gift
12 Days of Christmas Competition
This question is part of our holiday event
Win $40,000 in prizes: courses, tests, and more
User avatar
Saks116
Joined: 05 Apr 2022
Last visit: 20 Apr 2026
Posts: 41
Own Kudos:
22
 [1]
Given Kudos: 32
Location: India
Products:
Posts: 41
Kudos: 22
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
good question!

D

Prime no. > 10 when divided by 18, leaves the remnainder.

18 = 2*3*3

When divided by 18 leaves remainder ... 1,2,3,4...17
But it should be including the factors of 18 = 2*3*3.
So, 1,5,7,11,13,17.... these are the remainders which will be left out after considering the conditions of (>10).

Divide the prime nos.and check!
User avatar
adityaprateek15
Joined: 26 May 2023
Last visit: 21 Apr 2026
Posts: 346
Own Kudos:
170
 [1]
Given Kudos: 323
Location: India
GPA: 2.7
Products:
Posts: 346
Kudos: 170
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The generated number can be any prime number greater than 10.

Let r be the remainder when Prime# P is divided by 18

P = 18Q + R, we get 0<=R<18

Also, R = P - 18Q = odd - even = odd

Since P is not divisible by 3 and 18Q is divisible by 3, the difference R cannot be divisible by 3

Test Prime# greater than 10 and divide it by 18 to get the remainder..

Therefore, list of possible numbers with the above constraint are 1,5,7,11,13,17

Total 6.
Bunuel
A computer program randomly generates positive integers greater than 10 that have no factor p such that 1 < p < the generated number. Each time a number is generated, the program divides it by 18 and records the remainder. How many distinct remainders could the program possibly record?

A. 3
B. 4
C. 5
D. 6
E. 9

Gift
12 Days of Christmas Competition
This question is part of our holiday event
Win $40,000 in prizes: courses, tests, and more
User avatar
sureshkumark
Joined: 13 Aug 2011
Last visit: 20 Apr 2026
Posts: 10
Own Kudos:
5
 [1]
Given Kudos: 9
Products:
Posts: 10
Kudos: 5
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Positive integers greater than 10 and have no factors 1<p<generated number which means the generated numbers are prime numbers greater than 10.. So, let's take 11/18= remainder-11 : 13/18=remaninder-13 : 17/18= remainder-17, 19/18=remainder-1 : 23/18= reaminder-5: 97/18= remainder-7. So, there are 6 possible distinct remainders. So, the answer is choice : D..
User avatar
rutikaoqw
Joined: 29 Oct 2025
Last visit: 20 Mar 2026
Posts: 30
Own Kudos:
Given Kudos: 5
Location: India
Schools: ISB '27 IIM
GMAT Focus 1: 605 Q84 V82 DI72
GPA: 9.28
Schools: ISB '27 IIM
GMAT Focus 1: 605 Q84 V82 DI72
Posts: 30
Kudos: 16
Kudos
Add Kudos
Bookmarks
Bookmark this Post
A number that has no factor between itself and 1 is a prime number.
Trying to plot trends (since remainders are cyclic in nature)
Prime numbers greater than 10 are:
11: Remainder 11
13: Remainder 13
17: Remainder 17
19: Remainder 1
23: Remainder 5
29: Remainder 11 (repeating)
Hence 5 remainders
User avatar
Zeus_
Joined: 03 Jan 2024
Last visit: 12 Apr 2026
Posts: 17
Own Kudos:
Given Kudos: 6
Products:
Posts: 17
Kudos: 8
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
A computer program randomly generates positive integers greater than 10 that have no factor p such that 1 < p < the generated number. Each time a number is generated, the program divides it by 18 and records the remainder. How many distinct remainders could the program possibly record?

A. 3
B. 4
C. 5
D. 6
E. 9

Gift
12 Days of Christmas Competition
This question is part of our holiday event
Win $40,000 in prizes: courses, tests, and more

Integer N is prime since it doesn't have any factor except one and itself. So any prime number > 10 when divided by 18 would leave remainder as 11, 13, 17, 1, 5, 7

so 5 numbers in total.
User avatar
Reon
Joined: 16 Sep 2025
Last visit: 28 Mar 2026
Posts: 134
Own Kudos:
121
 [1]
Given Kudos: 4
Posts: 134
Kudos: 121
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
A computer program randomly generates positive integers greater than 10 that have no factor p such that 1 < p < the generated number. Each time a number is generated, the program divides it by 18 and records the remainder. How many distinct remainders could the program possibly record?

It only generates positive integers that have no factor p such that 1 < p < the generated number. Means it only generates prime greater than 10 like 11,13,17,19 and so on
Possible remainder when any number is divided by 18 = (0,1,2,3,4,....16,17)
Any prime greater than 10 is not even, so we can safely eliminate the even remainder like (0,2,4,6,8,10,12,14,16)
Any prime greater than 10 is not divisible by 3, so we can also eliminate (3,9,15)
Now, remaining we only have 6 possible remainders (1,5,7,11,13,17)
Or we can also try dividing primes greater than 10 by 18 to check the remainders.

D. 6
User avatar
ravi1522
Joined: 05 Jan 2023
Last visit: 21 Apr 2026
Posts: 172
Own Kudos:
Given Kudos: 5
Location: India
Concentration: General Management, General Management
GMAT Focus 1: 595 Q80 V83 DI76
GMAT 1: 530 Q38 V24
GPA: 7.2
WE:Design (Real Estate)
Products:
GMAT Focus 1: 595 Q80 V83 DI76
GMAT 1: 530 Q38 V24
Posts: 172
Kudos: 111
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hello,
So the number will prime greater than 10
so Number will be 11 , 13,17,19,23,29,31,
remainder will be when divided by 18
11,13,17,1,5, then again same pattern will be repeated

so answer is 5
Option C is correct
User avatar
redandme21
Joined: 14 Dec 2025
Last visit: 05 Jan 2026
Posts: 97
Own Kudos:
87
 [1]
Posts: 97
Kudos: 87
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The generated number n is a prime number greater than 10.

When n is divided by 18:

n = 18 * q + r with r<18

18 and r must not have any common factor. If they would have some common factor, for example "c", then:

n = c * ((18/c) * q + r/c)

And n would not be a prime number.

18=2*3^2 -> prime factors 2 and 3.

The possible values for r are the values less than 18 that do not have any prime factors of 18: 1, 5, 7, 11, 13, 17

Checking if the possible values are real values:

If n is 11, 13 or 17, then r is 11, 13 and 17 respectively.
If n is 19, then r is 1.
If n is 23, then r is 5
If n is 43, then r is 7

6 values

IMO D
User avatar
Vaishbab
Joined: 29 Jan 2023
Last visit: 08 Mar 2026
Posts: 115
Own Kudos:
51
 [1]
Given Kudos: 81
Location: India
Concentration: Strategy, Operations
Posts: 115
Kudos: 51
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I couldn't think of an easier way to do this. Had to brute force it.

Firstly, if a number has no factor 'p' between 1 & itself, it means it's a prime.

And when divided by 18, all possible remainders for numbers that are primes would be 1, 5, 7, 11, 13 & 17 (all other remainders would involve numbers divisible by 2 or 3).

Tested the 6 remainders with possible values and found primes that satisfied all 6.

Therefore, the answer is 6.
User avatar
geocircle
Joined: 14 Dec 2025
Last visit: 27 Dec 2025
Posts: 90
Own Kudos:
87
 [1]
Posts: 90
Kudos: 87
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The program generates prime numbers greater than 10, since a positive integer with no factor p such that 1<p<number is, by definition, prime.

number = quotient * 18 + remainder

The remainder must be coprime to 18 because, if it were not, then the common factor would be a divisor of the number and the number would not be prime.
The remainder must be less than 18.

18 has two prime factors, 2 and 3.
Coprimes of 18: 1,5,7,11,13 and 17

Each of these remainders does occur for some prime greater than 10.
The number of possible distinct remainders is 6.

Answer D
   1   2   3   4   5   
Moderators:
Math Expert
109718 posts
Tuck School Moderator
853 posts