Two numbers have HCF + LCM = 403 and also LCM = 12 times HCF. If one number is 93, find the other number.

Difficulty: Easy

Correct Answer: 124

Explanation:

Introduction / Context:This problem blends two key identities: (i) for two integers m and n, HCF * LCM = m * n, and (ii) here an extra relation LCM = 12 * HCF plus their sum. Using these, we can compute HCF and LCM first, then use the product identity to find the unknown integer directly.

Given Data / Assumptions:

  • H + L = 403.
  • L = 12H.
  • Known number = 93.

Concept / Approach:From L = 12H and H + L = 403, solve for H, L. Then use m * n = H * L to find the partner of 93: other = (H * L) / 93. Ensure the result is an integer to be consistent with integer inputs.

Step-by-Step Solution:

H + 12H = 403 ⇒ 13H = 403 ⇒ H = 31.Thus L = 12 * 31 = 372.Product m * n = H * L = 31 * 372 = 11532.Given one number is 93, the other = 11532 / 93 = 124.

Verification / Alternative check:

Check: HCF(93,124) = 31 and LCM = (93*124)/31 = 372. Sum 31 + 372 = 403 and 372 = 12 * 31, all satisfied.

Why Other Options Are Wrong:

  • 115, 122, 138 do not yield HCF 31 and LCM 372 with 93 under the product relation.

Common Pitfalls:

  • Mistakes in dividing 11532 by 93 or in solving 13H = 403.

Final Answer:

124

More Questions from Problems on H.C.F and L.C.M

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion