Last visit was: 10 Jun 2024, 22:22 It is currently 10 Jun 2024, 22:22
Decision Tracker
My Rewards
Unanswered
Active Topics
New posts
New comers' posts
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

Around the World in 80 Questions (Day 5): What is the number of

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 93658
Own Kudos [?]: 630754 [13]
Given Kudos: 82217
Send PM
CAT Tests Forum Quiz Mode
Around the World in 80 Questions (Day 5): What is the number of [#permalink] Around the World in 80 Questions (Day 5): What is the number of   21 Jul 2023, 08:00
1
Kudos
12
Bookmarks
Expert Reply
00:00
A
B
C
D
E

Difficulty:

35% (medium)

Question Stats:

68% (01:31) correct 32% (02:06) wrong based on 283 sessions
Hide Show DIFFICULTY AND TIMER STATISTICS
What is the number of positive factors of 900 that are multiples of 5?

A. 27
B. 21
C. 18
D. 15
E. 9



 


This question was provided by GMAT Club
for the Around the World in 80 Questions

Win over $20,000 in prizes: Courses, Tests & more

 



Experience a GMAT Club Test Questions
Yes, you've landed on a GMAT Club Tests question
Craving more? Unlock our full suite of GMAT Club Tests here
Want to experience more? Get a taste of our tests with our free trial today
Rise to the challenge with GMAT Club Tests. Happy practicing!
GMAT Club Tests Check Our Products Try Free Tests
ShowHide Answer
Official Answer
C
User avatar
G
Nabneet
Manager
Manager
Joined: 27 Dec 2022
Posts: 107
Own Kudos [?]: 79 [2]
Given Kudos: 40
Location: India
GMAT 1: 550 Q47 V20
WE:Other (Other)
Send PM
Re: Around the World in 80 Questions (Day 5): What is the number of [#permalink] Around the World in 80 Questions (Day 5): What is the number of   Updated on: 22 Jul 2023, 08:17
2
Kudos
Bunuel wrote:
What is the number of positive factors of 900 that are multiples of 5?

A. 27
B. 21
C. 18
D. 15
E. 9



 


This question was provided by GMAT Club
for the Around the World in 80 Questions

Win over $20,000 in prizes: Courses, Tests & more

 



\(900 = 2^2 * 3^2 * 5^2\)

Total no. of factors of 900 = (2+1)*(2+1)*(2+1)= 3*3*3 =27

No. of factors not multiple 5 = 2, 3, 2^2, 2^2 *3, 2^2 * 3^2 , 3^2 * 2, 3^2 =1,2,3,4,6,9,12,18,36

No of factors multiple of 5 = 27-9 =18

Answer: C

Originally posted by Nabneet on 21 Jul 2023, 08:51.
Last edited by Nabneet on 22 Jul 2023, 08:17, edited 2 times in total.
User avatar
D
$!vakumar.m
Director
Director
Joined: 06 Dec 2021
Posts: 505
Own Kudos [?]: 525 [2]
Given Kudos: 737
Location: India
Concentration: Technology, International Business
GPA: 4
WE:Human Resources (Telecommunications)
Send PM
GMAT ToolKit User
Re: Around the World in 80 Questions (Day 5): What is the number of [#permalink] Around the World in 80 Questions (Day 5): What is the number of   21 Jul 2023, 09:10
2
Kudos
Let’s find the prime factorization of 900.
900 = 2^2 * 3^2 * 5^2. The number of positive factors of 900 is (2 + 1)(2 + 1)(2 + 1) = 27.
Now, a positive factor of 900 that is a multiple of 5 must have at least one factor of 5.
So, the number of positive factors of 900 that are not multiples of 5 is (2 + 1)(2 + 1)(0 + 1) = 9.
Therefore, the number of positive factors of 900 that are multiples of 5 is 27 - 9 = 18.
Answer C
User avatar
G
sujoykrdatta
Tutor
Joined: 26 Jun 2014
Status:Mentor & Coach | GMAT Q51 | CAT 99.98
Posts: 450
Own Kudos [?]: 786 [2]
Given Kudos: 8
Send PM
Re: Around the World in 80 Questions (Day 5): What is the number of [#permalink] Around the World in 80 Questions (Day 5): What is the number of   26 Jul 2023, 20:40
2
Kudos
Expert Reply
Bunuel wrote:
What is the number of positive factors of 900 that are multiples of 5?

A. 27
B. 21
C. 18
D. 15
E. 9
 


This question was provided by GMAT Club
for the Around the World in 80 Questions

Win over $20,000 in prizes: Courses, Tests & more

 



900 = 2^2 * 3^2 * 5^2
Possible factors are formed by a combination of individual factors of the primes:
For 2: 2^0, 2^1, 2^2
For 3: 3^0, 3^1, 3^2
For 5: 5^0, 5^1, 5^2

Since we need the factors that are multiple of 5, the possible options for 5 must be 5^1 and 5^2 only
Thus, total number of combinations = 3 * 3 * 2 = 18
Answer C
GMAT Club Bot
gmatclubot
Re: Around the World in 80 Questions (Day 5): What is the number of [#permalink]
26 Jul 2023, 20:40
Moderator:
Bunuel
Math Expert
93658 posts