BN1989
If p and q are consecutive integers, is p a multiple of 3?
1) q is not a multiple of 3
2) q-1 is not a multiple of 3
In consecutive integer questions like this one,
is the order of the variables implied, meaning that p comes before q or could p come after q as well?
No, p and q are consecutive integers does not necessarily means that they are in that order: it could be (p, q=p+1) as well as (q, p=q+1). If it were otherwise then the answer to the question would be B, not E.
If p and q are consecutive integers, is p a multiple of 3?Out of three consecutive integers one is always multiple of 3. Now, there can be two cases.
A. (q-1,
q, q+1=p)
B. (
q-1=p, q, q+1)
(1) q is not a multiple of 3. Not sufficient.
(2) q-1 is not a multiple of 3. Not sufficient.
(1)+(2) Now, if we have case A, q-1 is not a multiple of 3 and q is not a multiple of 3, would mean that
p=q+1 must be a multiple of 3 BUT if we have case B, then q-1=p and (2) directly says that
q-1=p is not a multiple of 3. So, p may or may not be a multiple of 3. Not sufficient,
Answer: E.
Hope it's clear.