What is the 30th term of the arithmetic series 2, 5, 8, … ?

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Answer 1 · 2018-05-06T18:35:58

#a_30 = 89#

Given: arithmetic series #2, 5, 8#

arithmetic series have the form: #a^n = a_1 + (n-1)d#

#d = # the common difference

#d = a_2 - a_1 = a_3 - a_2 = 8-5 = 3#

#a^n = 2 + 3(n-1)#

To find the 30th term, let #n = 30#:

#a_30 = 2 +3(30 - 1) = 2 + 3(29) = 2 + 87 = 89#