Respuesta :

devishri1977

Answer:

Step-by-step explanation:

a1 = 5

common difference = 2nd term - 1st term= 14 -5 = 9

n = 31

[tex]S_{n}=\frac{n}{2}[2a+(n-1)d]\\\\S_{31}=\frac{31}{2}[2*5+30*9]\\\\=\frac{31}{2}[10+270]\\\\=\frac{31}{2}*280\\\\=31*140\\\\=4340[/tex]

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