City Of London - Q 26

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ReplayMum
Posts: 117
Joined: Tue May 10, 2011 2:12 pm

City Of London - Q 26

Post by ReplayMum »

Please can someone help us on this question.

A palindromic number is the same whether read it from left to right, or right to left. For example 41514 is a palindromic number.
Find as many whole numbers as you can which are:
a) greater than 1 and less than 500, and
b) palindromic, and
c) either a square number or cube numbers.

All help is appreciated.
Thank you.
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: City Of London - Q 26

Post by Guest55 »

Find as many whole numbers as you can which are:
a) greater than 1 and less than 500, and
b) palindromic, and
c) either a square number or cube numbers.
No square number less than 100 is palindromic so I'd list the square numbers great than 100 first

11 squared 121 OK
12 squared 144 no
13 squared 169 no
14 squared 196 no
15 squared 225 no
16 squared 256 no
17 squared 289 no
18 squared 324 no
19 squared 361 no
20 squared 400 no
21 squared 441 no
22 squared 484 OK

now the same with cubes
5 cubed 125 no
6 cubed 216 no
7 cubed 343 OK

So only three numbers I reckon ... 121, 343, 484
WP
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Location: Watford, Herts

Re: City Of London - Q 26

Post by WP »

plus 4, 8 and 9.

One can quickly eliminate the 2-digit palindromes by noting they all divide by 11.
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: City Of London - Q 26

Post by Guest55 »

WP - technically yes but some books do not allow single digits as palindromes.
ReplayMum
Posts: 117
Joined: Tue May 10, 2011 2:12 pm

Re: City Of London - Q 26

Post by ReplayMum »

thanks a lot Guest 55 & WP.
You guys are amazing.
Guest55
Posts: 16254
Joined: Mon Feb 12, 2007 2:21 pm

Re: City Of London - Q 26

Post by Guest55 »

I'm female btw :D
newbie2010
Posts: 11
Joined: Thu Sep 30, 2010 12:29 pm

Re: City Of London - Q 26

Post by newbie2010 »

Hi ReplayMum,

Please can you let me know where I can find this paper (City of London)?

Regards

newbie2010
ReplayMum
Posts: 117
Joined: Tue May 10, 2011 2:12 pm

Re: City Of London - Q 26

Post by ReplayMum »

Hi newbie 2010

If you search for City of London School for Girls in google, you should get the schools link.
Here you can download the papers, but unfortunately there are no answers provided.

Hope this helps.

ReplayMum
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