Liam is saving money to purchase a high-end camera. He saves 6.00 in week 1, 6.40 in week 2, 6.80 in week 3 and so on, continuing this pattern until he has enough total savings to buy the camera.
He decides to model his savings using either an arithmetic series or a geometric series. Using the information given,
(i) state with a reason whether an arithmetic series or a geometric series should be used,
(ii) write down an expression, in terms of nnn, for the amount, in pounds ( ), saved in week nnn.
Given that the camera Liam wants to buy costs 560, find the number of weeks it will take for Liam to save enough money to buy the camera.
178 exam-style questions on Edexcel A Level Maths Sequences and Series, covering 3.1 Arithmetic Sequences, 3.2 Arithmetic Series, 3.3 Geometric Sequences, 3.4 Geometric Series, 3.5 Sum to Infinity, 3.6 Sigma Notation, 3.7 Recurrence Relations, and 3.8 Modelling with Series. Each one has a worked solution and a mark scheme showing where the marks go.