A geometric series has a second term of 3 and its sum to infinity is 16.
Determine the two possible values of rrr.
Determine the corresponding two possible values of aaa.
Given that r r\,r takes the larger of the two possible values, find the smallest value of n n\,n for which Sn>15.5S_n > 15.5Sn>15.5.
231 exam-style questions on WJEC A Level Maths 3.4 Sequences and Series (A-level only), covering 3.4.1 Sequences and Series (A-level only), 3.4.2 Sequences and Series (A-level only), 3.4.3 Sequences and Series (A-level only), 3.4.4 Sequences and Series (A-level only), 3.4.5 Sequences and Series (A-level only), 3.4.6 Sequences and Series (A-level only), and 3.4.7 Sequences and Series (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.