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#1 2011-12-19 04:10:24

juantheron
Member
Registered: 2011-10-19
Posts: 312

middle one is perfect square

find three digit numbers in which the middle one is a perfect square are formed using the digits 1 to 9

and also find sum of their digits

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#2 2011-12-19 04:53:20

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: middle one is perfect square

I don't understand the question.  Are you asking us to find all of the three digit numbers where the middle digit is a perfect square?  Like 142, the middle digit 4 is a square, is that what you need?


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#3 2011-12-19 05:14:26

juantheron
Member
Registered: 2011-10-19
Posts: 312

Re: middle one is perfect square

yes you are saying right

Are you asking us to find all of the three digit numbers where the middle digit is a perfect square?  Like 142, the middle digit 4 is a square

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#4 2011-12-19 05:45:02

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: middle one is perfect square

hi juantheron

when you wanna quote someone you should use

tags.

second of all,there are 9*4*10=360 numbers satisfying the conditions.


“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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#5 2011-12-19 05:54:27

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: middle one is perfect square

He said using digits 1-9, so it would be 9*3*9 = 243 numbers.  Also juan, when you say you want to find the sum of their digits, do you mean the total sum of the digits of all 243 of those numbers?

Last edited by TheDude (2011-12-19 05:54:49)


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#6 2011-12-19 06:00:15

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: middle one is perfect square

hi TheDude

didn't see that.yes there are 243 such numbers.

hi juantheron

if it's like thedude said sum of digits of all those numbers together then it's:

81*1+81*4+81*9+27*45+27*45=3564 ... if i calculated it correctly big_smile


“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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#7 2011-12-19 15:20:15

juantheron
Member
Registered: 2011-10-19
Posts: 312

Re: middle one is perfect square

thanks to all

can any one explain me how can i get such no.

and their sum

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#8 2011-12-19 20:41:45

Bob
Administrator
Registered: 2010-06-20
Posts: 10,583

Re: middle one is perfect square

hi juantheron


This question seems very odd.  There are too many answers.  sad

Are you sure you have written it correctly?

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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