Elitmus
Exam
Numerical Ability
Number System
x lies from 121 < x >1331, x^2+1 when divided by 11 what will not be the remainder .
A.1 b.4 c.6 d.8
Read Solution (Total 4)
-
- since x should be greater than 121, let us suppose that 'y' is no. which is greater than 0,
now we can write, x^2+1 as (121+y)^2 +1.
(y^2 + 121^2 + 2*121*y + 1)/11
y^2/11 + 121^2/11 + 2*121*y/11 + 1/11
y^2/11 + 0 + 0 + 1 ( remainder)
y^2/11 + 1
y^2 can be 1,4,9,16,25......
after dividing by 11,remainder we got 1,4,6 but not 8.
so ans is d. - 7 years agoHelpfull: Yes(19) No(6)
- Vikash Please clarify
since x should be greater than 121, let us suppose that 'y' is no. which is greater than 0,
now we can write, x^2+1 as (121+y)^2 +1.
(y^2 + 121^2 + 2*121*y + 1)/11
y^2/11 + 121^2/11 + 2*121*y/11 + 1/11
y^2/11 + 0 + 0 + 1 ( remainder)
y^2/11 + 1
y^2 can be 1,4,9,16,25......
after dividing by 11,remainder we got 1,4,6(is it 6 or 9),5.... and we should add +1 also to this right because of 1/11 ?? - 7 years agoHelpfull: Yes(5) No(1)
- option d>8
- 7 years agoHelpfull: Yes(1) No(0)
- how u got ths
- 7 years agoHelpfull: Yes(0) No(0)
Elitmus Other Question