Directions: Given below there are three number series (I, II, and III).

One of the numbers in each series (I, II, and III) is wrong 

Series I: 24, 12, 12, 18, 36, 80

Series II: 289, 310, 275, 320, 269, 330

Series III: 10, 12, 68, 30, 220, 56

A, B & C are the correct terms of the series I, II & III.

then,

I. C + A - 33 = B

II. B + 1721 = (A)2 - 6000 - C

III. (A + B + C)/3 = 197

Which of the above three equations is incorrect?