Maths  Arithmetic Progression
posted by Chrissey on .
The fourth term of an AP is 8 and the sum of the first ten terms is 40. Find the first term and the tenth term.

T4 = a+3d = 8
S10 = 5(2a+9d) = 40
a = 16
d = 8/3
T1 = 16
T10 = 16 + 9(8/3) = 8
check, sequence is
16 40/3 32/3 8 16/3 8/3 0 8/3 16/3 8 ...
Sum of 1st 10 terms = 40