Question

an = a1 + ( n -1 ) . r a1= -14 / an= 19 / r= 3 / n= ?

Answer 1

a1 - 14    an = 19   r = 3 n = ?

a1 + (n - 1) .r = an
-14 + ( n - 1).3 = 19
(n - 1).3 = 19 + 14
(n - 1).3 = 33
n - 1 = 33/3
n - 1 = 11
n = 11+1
n = 12                

PA(  - 14, - 11, - 8, - 5, - 2, 1, 4, 7, 11, 13, 16, 19 )