Question

9, 4, -1, -6, -11, . . . Find the 27th term of the given A.P.

Answer 1

Given A.P is

9 , 4 , -1 , -6 , -11 , ...,

First term = a = a1 = 9

Second term = a2 = 4

Common difference ( d ) = a2 - a1

d = 4 - 9

d = - 5

nth term = an

an = a + ( n - 1 )d

Here , n = 27

s27 = 9 + ( 27 - 1 )( -5 )

= 9 + 26( -5 )

= 9 - 130

= -121

Therefore ,

27th term of A.P = a27 = -121

••••

Answer 2

Answer:

The given sequence is 9, 4, –1, –6, –11,...

Here,

First term (a) = 9

Common difference (d) = a2 – a1 = 4 – (9) = –5

Now,

a27=a+(n−1)d    

 =9+(27−1)(−5)    

=9+(26)(−5)    

 =−121

Hence, the 27th term of the progression is –121.

Step-by-step explanation: