# SPM Practice 1 (Arithmetic Progression) : Question 13

Question 13

An arithmetic progression has 9 terms. The sum of the first four terms is 24 and the sum of all the odd number terms is 55. Find
(a) The first term and common difference,
(b) The seventh term.

Hint : If an arithmetic progression has 9 terms
The sum of the even number terms = ${T}_{2}+{T}_{4}+{T}_{6}+{T}_{8}$
The sum of the odd number terms =  T 1 + T 3 + T 5 + T 7 + T 9