SI on a sum for some months at a given rate

The same question, asked 3 times: 19 Jul 2023 S1*, 27 Jul 2023 S1*, 12 Sep 2024 S3. Every wording below, oldest first.

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Question 1
19 Jul 2023 S1
69 $How much simple interest will ₹6,000 earn in 21 months at 8% per annum?$
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Question 2
27 Jul 2023 S1
65 $14\frac{2}{3}\%$
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Question 3
12 Sep 2024 S3
55 $12\%$
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