Liam starts a training program where he runs 150 km in the first month and increases his monthly distance by 25 km each subsequent month. Sarah also starts a training program; she runs 210 km in the first month and increases her monthly distance by 15 km each subsequent month.
After how many months have Liam and Sarah run the same total distance.
326 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.