Quantitative Aptitude - Numbers and Algebra
- Option : A
- Explanation :
Number is 120K + 1= ((13 * 9 + 3) K + 1)
= 13 * 9K + 3 K + 1, which is divisible by 13.
3K + 1 is divisible by 13.
∴ K = 4. Number = 481
- Option : A
- Explanation : I. In case all the remaining three numbers are multiples of the prime number, HCF of the group is equal to that prime number. otherwise HCF of the group is 1. Thus, I is true.
II. Case 1: Let numbers be 2, 4, 6 and 8, where 2 is only prime number, then LCM = 24.
But LCM of 4, 6 and 8 = 24.
Case 2 : Let numbers be 2, 9, 81 and 27 Then LCM = 162 and LCM of 9, 81 and 27 = 81.
Thus, LCM = 81 * 2 = 162 Hence II is not always true.
III. Let numbers be 2, 4, 6 and 8 LCM =24 and HCF = 2 Product of four numbers = 2 *4 * 6 * 8= 384
Also, 384 ≠ 24 * 2 * 2. Thus, III is not true.
