The average of the first 7 non-zero multiples of 17 is:

67 68 69 66

68

Sum of A.P = \(\frac{n}{2}\) ( 2a + (n - 1)d ) Sum of 1st 7 multiples of 17 = \(\frac{7}{2}\) ( 2 x 17 + 6 x 17 )                                           ⇒ 476 Average of 1st 7 multiples of 17 = \(\frac{476}{7}\) = 68