Question

Tobi is training to run a marathon. In the first week she runs 25 km and increases this distance by 10% each week. This situation may be modelled by the series 25 + 25(1.1) + 25(1.1)2 + . She wishes to continue this pattern for 14 weeks. How far will she have run in total when she completes the 14th week? Express your answer to the nearest tenth of a kilometre.

Answer 1

just use what you know about geometric sequences:

S14 = 25(1.1^14-1)/(1.14-1) = 499.55 km

Answer 2

Kane is training for a marathon. He starts by running 3 miles during every training session each week plans to increase the distance of his runs by 1/4 mile. Let w be the number of weeks. Write and expression to show the diatance kane runs in a training session after w weeks