Question 856145
How can we tell you what you did wrong, if you don't show us what you did?
S = ½(2a + (n-1)d)n
S = ½(2*8 + (21)6)22
S = 1562

or another way
Find a22
an = a + (n - 1)d
a22 = 8 + (21)6
a22=134
now find the sum
S = ½(a + an)n
S = ½(8 + 134)22
S = 11(142)
s=1562