Not sure if this is THE most optimal but here goes...gmatme wrote:What is the remainderwhen a positive integer x is divided by 8?
a) When x is divided by 12 the remainder is 5
b) When x is divided by 18 the remainder is 7
What is the best and quick way to solve this problem?
1 - insufficient.
x = 12*t + 5
We have to find remainder of x / 8
For even values of t, remainder = 5. For odd values of t, remainder = 1
2 - insufficient.
x = 18*s + 7
Try s=0, s=1, s=2, s=3. We get remainders of 7, 1, 3 and 5 resp.
Together they are insufficient as well since remainder can be 1 or 5.
Hence E
