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

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

Answer»

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

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