Question

Write 5^th term from the end of the A.P. 3, 5, 7, 9, ...., 201.

Answer 1

Here a = 201, 

a₂ = 5, 

a₃ = 7 

d = a₃ – a₂ = a₂ – a₁ 

= 7 – 5 = 5 – 3 = 2 

t_n = a + (n –1)d 

t_n = 3 + (n–1)2 = 201 

(n –1)2 = 201 – 3 = 198 

n – 1 =\(\frac{198}{2}\) = 99 

n = 99 + 1 =100 

5^th term from end = 96^th term 

T₉₅ = 3 + (96 –1)2 

T₉₅ = 3 + 95 x 2 

T₉₅ = 3 + 190 = 193