Question

Na PA (4 8 12...)

a) A200

b) A84

c)A27

Answer 1

P.A.(4;8;12;............)
R = A 2 - A 1
R = 8 - 4
R = 4
a)  A 200
A 200 = A 1 + (N - 1 ) . R
A 200 = 4 + (200 - 1 ) . 4
A 200 = 4 + 199 . 4
A 200 = 4 + 796
A 200 = 800
b)A 84
A 84 = A 1 + ( N - 1 ) . R
A 84 = 4 + (84 - 1 ). 4
A 84 = 4 + 83 . 4
A 84 = 4 + 332
A 84 = 336

c)A 27
A 27 = A 1 + (N - 1 ).R
A 27 = 4 + (27 - 1 ) . 4
A 27 = 4 + 26 . 4
A 27 = 4 + 104
A 27 = 108