ExpertsGlobal5
If \(a\), \(b\), \(c\), and \(d\) are four integers greater than 1, which of the following
cannot be a multiple of
any of \(a\), \(b\), \(c\), or \(d\)?
A. \(\frac{a }{ b}\) + \(\frac{c }{ d}\)
B. \(\frac{a }{ b}\) – \(\frac{c }{ d}\)
C. \(abcd\) + 2
D. \(abcd\) – 1
E. \(abcd\) + 10
Let us begin by considering Options C and E.
If any one of the integers \(a\), \(b\), \(c\), or \(d\) equals 2, then both \(abcd\) + 2 and \(abcd\) + 10 become even, and therefore are multiples of 2. This means that, under an appropriate choice of values, Options C and E can be multiples of at least one of the four integers. Thus, we eliminate C and E.
Let's take Option D: \(abcd\) – 1.
Since \(abcd\) is the product of the four integers, it is guaranteed to be a multiple of each of \(a\), \(b\), \(c\), and \(d\). For the entire expression \(abcd\) – 1 to be a multiple of any of these integers, the term 1 would also need to be a multiple of at least one among \(a\), \(b\), \(c\), or \(d\). However, the problem explicitly states that all four integers are greater than 1, which makes this impossible because 1 cannot be a multiple of any integer greater than 1.
Option D