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Numerical Ability
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5. Sum of the digits of a three digit number is 17. Sum of squares of digits of the given number is 109. If we subtract 495 from that number we will get a number written in reverse order. Find the number.
Read Solution (Total 9)
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- let a,b,c
a+b+c=17....eq1
a^2+b^2+c^2=109......eq2
100a+10b+c-495=100c+10b+a.......eq3
eq3- 99a-99c=495
a-c=5
a=5+c
for c=1 a=6 and b=10 but eq2 not true.
for c=2 a=7 and b=8 but eq2 not true
for c=3 a=8 and b=6 so eq2 is true
digit is 863 ans - 11 years agoHelpfull: Yes(32) No(2)
- 863,
SINCE, 8^2+6^2+3^2=109 ,
AND 863-495=368,
SO, NUMBER IS 863 ANS. - 11 years agoHelpfull: Yes(7) No(0)
- dummy question.....just do option verification...u don't need any tricks.
- 11 years agoHelpfull: Yes(3) No(0)
- 863
take 3 digit as a+b+c=17
sum of square is a^2+b^2+c^2=109
100a+10b+c-495=100c+10b+a
99(a-c)=495
a-c=5
- 11 years agoHelpfull: Yes(1) No(5)
- no. is 863 8*8+6*6+3*3=109
863-495=368 - 11 years agoHelpfull: Yes(1) No(3)
- 8+6+3=17
now by squaring we get=64+36+9=109
now 863-495=368
so by subs. we are getting the reverse of that no.
- 11 years agoHelpfull: Yes(0) No(1)
- 863 863-495=368 proved
- 11 years agoHelpfull: Yes(0) No(1)
- u can go with the given answer...
this is the best way to find the no... - 11 years agoHelpfull: Yes(0) No(0)
- 782-495=287
- 10 years agoHelpfull: Yes(0) No(0)
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