Across a 21-day training spell, an athlete gets ready for a marathon by adding $1.2\text{ km}$ to the distance she covers each day. On day 1, she runs $13\text{ km}$.
(a(i))[1]
Determine the distance she runs on the final day of the 21-day period.
(a(ii))[2]
Determine the total distance she runs over the 21-day period.
(b(i))[2]
The first three terms of a geometric progression are $x$, $x - 3$ and $x - 5$ respectively. Find the value of $x$.
(b(ii))[2]
Find the progression's fourth term.
(b(iii))[2]
Determine the sum to infinity of the progression.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “The correct 21st term is $37$” …