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Q. Find the 3 digit no. whose last digit is the squareroot of the first digit and second digit is the sum of the other two digits
Read Solution (Total 16)
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- let xyz be the digits of no.,then
z=sqrt(x)
y=x+z=x+sqrt(x)
so no. is =100x+10y+z
=100x+10(x+sqrt(x))+sqrt(x)
=110x+11*sqrt(x)
if x=1, no. is =121
if x=4, no. is =462
if x=9, no. is =990+33=1023(not 3 digit)
two no's 121 & 462 - 11 years agoHelpfull: Yes(41) No(0)
- 3 digit number
so __ __ __
in that gap we get
(x) (x+sqrt(x)) sqrt(x)
digits are 0,1,2,3,4,5,6,7,8,9
sqrt applicable for 1,4,9
first take 1 then number is 121
second take 4 then number is 462
third take 9 then number is 9123 which is not 3 digit numb
so ans is 121 and 462 - 11 years agoHelpfull: Yes(11) No(2)
- let first digit be a then the number will be a (a+root(a)) root(a)
if a=4
then root(a)= 2
a+root(a)=6
for any other value of a value of a+root(a) will not be a single digit and the number has to be a 3 digit number
so, the number will be 462 - 11 years agoHelpfull: Yes(5) No(1)
- single digit that must be square of other digit ,only 4 and 9 is on focus.
hence as per given terms,that nuber looks somewhat
4_2 or 9_3;
but middle is sum of other two number hence,
9+3=12 is not possible,
the digit is
462 - 11 years agoHelpfull: Yes(3) No(0)
- lets 3 digit no is xyz
z=squareroot(x)
y=x+z
lets consider x=1
z=squareroot(1)=1
y=1+1
so ans is 121 - 11 years agoHelpfull: Yes(1) No(0)
- digits are : x^2 x^2+x x
possible no.: 1 2 1
4 6 2
ans is 121 & 462 - 11 years agoHelpfull: Yes(1) No(0)
- 462
Last digit is square root of first digit
And second digit is the sum of first and last - 11 years agoHelpfull: Yes(0) No(0)
- let first term be x and last term be squareroot of x then middle term is (x)+ root(x). Then that 3 digit no must be 121 or 462
- 11 years agoHelpfull: Yes(0) No(0)
- 462 and 121
- 11 years agoHelpfull: Yes(0) No(0)
- either 121 or 462
- 11 years agoHelpfull: Yes(0) No(0)
- 462
last digit=square root 4
second digit=4+2=6
so,ans 462 - 11 years agoHelpfull: Yes(0) No(0)
- Its a 3 digit no. So for a square root to be single digit we can consider 3 no.'s 1,4,9 having sq. root 1, 2, 3 respectively.. 9 should not be considererd bcoz sum of first & last digit(9+3=11) will not be single digit.
We are left with 1 & 4.
For 1, no. would be 121(1st digit, sum of 1st & last digit, squareroot of 1st digit)
For 4, it would be 462 similarly
Answer should be either 121 or 462 - 11 years agoHelpfull: Yes(0) No(0)
- As per question third digit may be 1,2,3.
So first digit will be
if last digit is 1-> 1_1,
if last digit is 2-> 4_2,
if last digit is 3-> 9_3.
Given 2nd digit is sum of first and second, Therefore add first and last digit. With this condition last digit as 3 is not satisfied because 9+3 = 12. And condition for last digit 1, 2 satisfies wrt question.
Ans- 121 (last digit sqr(1), second digit = sum of 1st and last i.e, 1+1 = 2)
462 (last digit sqr(4), second digit = sum of 1st and last i.e, 4+2 = 6) - 11 years agoHelpfull: Yes(0) No(0)
- answer will be 462
- 11 years agoHelpfull: Yes(0) No(0)
- 001, square root of 0+1 is 1 and sum of 0+1 is 1
- 10 years agoHelpfull: Yes(0) No(1)
- its 121 & 264
- 10 years agoHelpfull: Yes(0) No(0)
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