Of the three numbers, the sum of the first two is 73; the sum of the second and the third is 77 and the sum… · ABC26GN1773
Subject: General Aptitude · Chapter: Problems on Numbers · Exam: NABARD 2008
Of the three numbers, the sum of the first two is 73; the sum of the second and the third is 77 and the sum of the third and thrice the first is 104. The third number is
(a)25
(b)39
(c)48
(d)Cannot be determined
(e)None of these
Answer
Answer (as printed): E
Explanation
Let the numbers be $x, y$ and $z$. Then, $x+y=73$, $y+z=77$ and $3x+z=104$. ∴ $y=73-x$, $z=77-y=77-(73-x)=4+x$. ∴ $3x+4+x=104 \Leftrightarrow 4x=100 \Leftrightarrow x=25$. $y=(73-25)=48$ and $z=(4+25)=29$. ∴ Third number = 29.
Explanation as extracted from the printed page; notation may be imperfect.