Question
The HCF of two numbers is 84, and their LCM is 2520.
What is the sum of the numbers?Solution
Let the two numbers be 84x and 84y.
Then,
Product of the numbers = Product of HCF and LCM
84x × 84y = 84 × 2520
xy = 30
Let x = 5 and y = 6 (As co-prime factors of 30 are 5 and 6).
Then, the sum of the numbers is
84 × 5 + 84 × 6 = 84 × 11 = 924
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