eladshush wrote:

a,b,c are consecutive integers , so that a < b < c

Is the product a*b*c divisible by 8?

1. a*b*c is divisible by 12

2. b is a prime number

The answer is C

1. a *b*C is divisible by 12 - Insufficient

if a,b,c =3,4,5 ---------- not divisivle by 8

if a,b,c =7,8.9 ----------- divisible by 8

2. b is a prime number --- Insufficient

let us consider primes --- 2,3,5,7,11,.............

if we consider even prime i.e. 2

a,b,c =1,2,3

abc is not divisible by 8

if b=3

a,b,c =2,3,4

and abc=24 which is divisible by 8

if we consider 1 & 2 together abc is divisible by 12 and b is prime it will eliminate considering b as 2 because when b is 2 abc =6 which is eliminated.

so now abc is always multiple of 8