The H.C.F. of two numbers is 23 and the other two factors of their L.C.M. are 13 and 14. Find the larger number.
Aptitude
Problems on H.C.F and L.C.M
Difficulty: Medium
Choose an option
-
A299
-
B322
-
C345
-
D391
Answer
Correct Answer: 322
Explanation
Given data
- H.C.F. = 23
- The co-prime parts contributing to L.C.M. are 13 and 14.
Concept / Approach
- If HCF = h and the co-prime parts are p and q, the numbers can be taken as h·p and h·q (since gcd(p, q) = 1).
Step-by-step calculation
Numbers: 23×13 = 299 and 23×14 = 322L.C.M. = 23×13×14 and H.C.F. = 23, as required.
Verification
gcd(299, 322) = 23 (since 299 = 23×13 and 322 = 23×14).
Common pitfalls
- Multiplying 13 and 14 again into a single number, which is not the intent.
Final Answer
Larger number = 322.