Q19 of 167 Page 19

The first term of an A.P. is 2, and the last term is 50. The sum of all these terms is 442. Find the common difference.

given a1 = 2 and an = 50

To find: the common difference


we know that the sum of AP is given by the formula:



substituting the values in above equation we get



n = 17


Now for the finding number of terms, the formula is



we know that


d = 3


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