Question

the fourth term of the sequence is 19 and the eleventh term is 54. find the eighth term.

Answer 1

look like an arithmetic series: common difference = 54-19 / 11-4 = 35/7 = 5
eight term = 19 + 4(5) = 39

Answer 2

\[a _{n}=a _{1}+(n-1)d\]

Answer 3

so
\[a _{4}=a _{1}+3d=19\]

Answer 4

and
\[a _{3}=a _{1}+2d=54\]

Answer 5

so a1=54-2d=19-3d
a1=-35
d=18

Answer 6

so a11=-35+10*18
=-35+180
=145

Answer 7

am not sure u got it .......pls check the question again