This is an interesting counting methods question that combines a very basic rule of test of divisibility of number by 3. Question How many six digit positive integers comprising only the digits 1 and 2 can be formed such that the number is divisible by 3? 3 20 22 38 360 Correct Answer Choice C. 22 such numbers can be formed. Video Explanation Explanatory … [Read more...] about Permutation of Digits & Divisibility