Question 636692
nth term:


an = a1 + (n-1)*d


an = 3 + (n-1)*4


an = 3 + 4n - 4


an = 4n - 1


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15th term


an = 4n - 1


a15 = 4(15) - 1


a15 = 60 - 1


a15 = 59