Question

11,8,5,2,..Inthis A. P. which term is number - 151​

Answer 1

ii). A.P. is 3, 8, 13, ..., 253 ... Here let us write the series in this form, ..... ∴The 25th term of the A.P. ...

Answer 2

Answer :-

⏩Given that

11 , 8 , 5 , 2 ... is in AP

◾And it's asked that -151 is which term

♦ So before solving we must find out the common difference

◾Which is term2 - term1

= 8 - 11

= -3

⏩Now we will find out the required answer

◾As we we know

$a_n = a + (n - 1)d$

◾Where

$\tt{ a_n = n^{th} \:term}$

→a = first term

→d = common difference

So by substiting value

$\sf{ -151 = 11 + ( n-1)(-3) }$

$\implies \sf{ -151 = 11 - 3n + 3 }$

$\implies \sf{ -151 = 14 - 3n }$

$\implies \sf{ -151 - 14 = - 3n}$

$\implies \sf{- 165 = -3n}$

$\implies \sf{\dfrac{-165}{-3} = n}$

$\implies \sf{ 55 = n}$

♦ So -151 is 55 th term of AP