Last visit was: 25 Nov 2024, 08:59 It is currently 25 Nov 2024, 08:59

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
avatar
Intern
Intern
Joined: 06 Oct 2017
Posts: 9
Own Kudos [?]: 13 [3]
Given Kudos: 0
Send PM
Verbal Expert
Joined: 18 Apr 2015
Posts: 30022
Own Kudos [?]: 36392 [0]
Given Kudos: 25928
Send PM
avatar
Intern
Intern
Joined: 06 Oct 2017
Posts: 9
Own Kudos [?]: 13 [0]
Given Kudos: 0
Send PM
avatar
Intern
Intern
Joined: 20 Mar 2018
Posts: 39
Own Kudos [?]: 127 [4]
Given Kudos: 0
GRE 1: Q163 V149

GRE 2: Q168 V162
GPA: 3.5
Send PM
Re: How many positive integers less than 1000 have a 5th root? [#permalink]
4
1) We need to find the numbers with 5th root and are less than or equal to 1000. So let's say the number is x. It can be written as n^5 where n is a natural number.
So, n^5 <= 1000 gives n=1, 2, 3 as 1^5 = 5, 2^5 = 32, 3^5 = 243. But 4^5 = 1024 which is greater than 1000.

Hence the answer is 3. The numbers are 1, 32 and 243

2) We need to find the numbers with square root and cube root and are less than or equal to 1000. Again let's say the number is x.
x can be written as: ((n)^2)^3. Square of any natural number and then the cube of that number, since we have to take a cube root and a square root. So, it becomes effectively n^6 <= 1000. We can now solve it. The total number of such numbers is 3 again.
1^6 = 1
2^6 = 64
3^6 = 729
User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 5054
Own Kudos [?]: 75 [0]
Given Kudos: 0
Send PM
Re: How many positive integers less than 1000 have a 5th root? [#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 positive integers less than 1000 have a 5th root? [#permalink]
Moderators:
Retired Moderator
6218 posts
Moderator
1111 posts
Retired Moderator
187 posts
Retired Moderator
348 posts
Retired Moderator
160 posts
GRE Instructor
117 posts
Retired Moderator
63 posts
Retired Moderator
1307 posts

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