Q2 of 50 Page 26

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

a = 1 S4 = 100 n = 4


Sn =


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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