Arithmetic Sequence

Question

Find the 19 ^th term of the arithmetic sequence 

Answer 1

Given AP -4, -1 1/3, 1 1/3, 4...........

t1  =  a  =  -4

t2  =  -1 1/3

d  =  t2 - t1

    =  -1 1/3  -  (-4)

    =  -4/3 + 4

    =  (-4 + 12) / 3

d  =  8 / 3

nth term tn = a + (n-1)d --------------> (1)

Substitute a  =  -4 and d  =  8/3 and n = 19 in Eq (1)

t19  =  -4 + (19-1)(8/3)

       =  -4 + 18(8/3)

       =  -4 + 48

t19  =  44

Amswer :

The 19th term is 44.