Question

please answer me fast guys 19

Answer 1

an=a+(n-1)d
33=8=(n-1)d
(n-1)=25         ........(i)

Sn=123
123=n/2(2a+(n-1)d)
      =n/2(16+25)     ........(from i)
     =41n/2=123
   therefore, n=6

using n=6 in (i)
25=5d
d=5