If y = 0.jkmn, where j, k, m, and n each represent a nonzero digit of y, what is the value of y ?
(1) j < k < m < n. Many combinations are possible: 1<2<3<4, 2<3<4<5, 1<3<4<5, ... Not sufficient.
(2) j + a = k, k + a = m, and m + a = n, where j > a > 1.
Since \(j+a=k\) and \(j\) and \(k\) represent digits then \(a\) must be an integer.
Next, since \(j > a > 1\) then the least value of \(a\) is 2 and the least value of \(j\) is 3.
So, from \(j+a=k\) the least value of \(k\) is 3+2=5, from \(k + a = m\) the least value of \(m\) is 5+2=7 and from \(m + a = n\) the least value of \(n\) is 7+2=9.
Now, if our initial number, \(a\), is more than 2, 3 for example, then the values of all other variables will increase and \(n\) will become more than 9, which is not possible since each variable represents a single nonzero digit.
Hence: \(j=3\), \(k=5\), \(m=7\), and \(n=9\). Sufficient.
Answer: B.