Cambridge IGCSE. 2025. Mathematics (0580). May/June - Paper 4 (41) · Calculator (Extended) - Question 10

**(c)** The **sum of the first *n* terms** of another sequence is $\dfrac{n}{2}(5n - 1)$.

**(ii)** Find the 3rd term of this sequence.

(In part (c)(i) you found that the sum of the first two terms is 9.)