The sum of first 10 even whole numbers is

The sum of first 10 even whole numbers is
(a) 110
(b) 90
(c) 55
(d) 45

Solution:

The list of number , , 1, – 3,… is a
(a) GP. with r = – 3
(b) G.P. with r =
(c) GP. with r = 3
(d) not a G.P.

Solution:

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