Answer:
1472
Step-by-step explanation:
The sum of n terms of an arithmetic sequence is
[tex]S_{n}[/tex] = [tex]\frac{n}{2}[/tex] [ 2a₁ + (n - 1)d ]
where a₁ is the first term and d the common difference
Here a₁ = 9 and d = 19 - 14 = 5 , thus
[tex]S_{23}[/tex] = [tex]\frac{23}{2}[/tex] [ (2 × 9) + (22 × 5) ]
= 11.5 (18 + 110) = 11.5 × 128 = 1472
