HCF and LCM from their sum and difference (or ratio): find the other number

The same question, asked 2 times: CDS 2 2020*, CDS 2 2021. Every wording below, oldest first.

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Question 1
CDS 2 2020
9 $LCM of two numbers is 28 times their HCF. The sum of the HCF and the LCM is 1740. If one of these numbers is 240, then what is the other number ?$
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Question 2
CDS 2 2021
5 $The sum of LCM and HCF of two numbers is 536 and the difference between LCM and HCF is 296. If one of the numbers is 104, then what is the other number ?$
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