Question

sum of first 12 terms of arithmetic sequence is 39/20 . and the sum of first 15 term is 3 then...
a)What is the 8th term?
b)What is the sum of 5th and 8th terms?
c)What is 5th term?
d)what is the common difference?
e)What is the 40th term?
please answer fast!

Answer 1

s12=39/20
s15=3
a+11d__39/20
a+14d___3
14d-11d__3d
39/
20-3__-21/20
subtraction
-7/20
a__79
a8_a+7d
put values answer will come