Question

N=(323232…….. 50 digits)₉.ie in base 9. Find the remainder when N is divided by 8?

• A. 1
• B. –1
• C. 0
• D. 3
• E. None of these

Answer 1

The correct option is D 3

In base 9, divisibility check for 8 is sum of the digits(digit sum) = Digit sum of N = (25*3 + 25 *2)₉ =

First convert the numbers to base 10

25 in base 10 = 23, Thus the question changes to (23*3 +23*2)₁₀ = 115₁₀

Converting it back to base 9 = 137, Now sum of digits in base 9 = 1+3 +7 = (4+ 7)₉ = 12 ⇒ =3