Subject: General Aptitude · Chapter: Number System · Exam: · Marks: · Difficulty:
There are just two ways in which 5 may be expressed as the sum of two different positive (non-zero) integers, namely $5=4+1=3+2$. In how many ways, 9 can be expressed as the sum of two different positive (non-zero) integers?
(a)3
(b)4
(c)5
(d)6
Answer
Answer (as printed): B
Explanation
We can write $9=(1+8) ; 9=(2+7)$; $9=(3+6), 9=(4+5)$. Thus, it can be done in 4 ways.
Explanation as extracted from the printed page; notation may be imperfect.