Triangle inequality: possible values of the third side

This type of question, asked 4 times: 17 Jul 2023 S2, 20 Jul 2023 S3, 17 Sep 2024 S3, 25 Sep 2024 S1. All 4 questions below, oldest first.

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Question 1
17 Jul 2023 S2
51 $The lengths of the three sides of a triangle are 30 cm, 42 cm and x cm. Which of the following is correct?$
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Question 2
20 Jul 2023 S3
62 $The three sides of a triangle are 12, 17 and x units. Which of the following options is correct?$
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Question 3
17 Sep 2024 S3
54 $In a triangle, the lengths of sides are 6 units, 12 units and x units. How many possible integer values are there for x?$
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Question 4
25 Sep 2024 S1
73 $If the lengths of two sides of an isosceles triangle are 6 cm and 12 cm, then find the length of the third side.$
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Question 1