Q. 23.6( 5 Votes )

# The first term of an arithmetic sequence is 1 and the sum of the first four terms is 100. Find the first four terms.

Answer :

a = 1 S_{4} = 100 n = 4

S_{n} =

Substituting everything in above equation,

2a + (4-1) × d = 50

∴ 3d = 48

∴ d = 16

First four terms are 1,17,33,49.

Hence, the answer is written above.

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