Question

Find a number r such that 0 ≤ r < 9 such that
77 · 139 · 38 · 107 ≡ r ( mod 9).

Answer 1

do i find the canonical representatives of the numbers in Z9?

Answer 2

hey secret! tag ganeshie8 !!! ;)

Answer 3

...they are not online

Answer 4

it might help to reduce every large number as much as possible

examples:

77 = 5 (mod 9) since 77/9 = 8 remainder 5
139 = 4 (mod 9) since 139/9 = 15 remainder 4
etc etc

Answer 5

"do i find the canonical representatives of the numbers in Z9?"

Yeah i think so. I'm not familiar with the technical term, but I think that's the same as going from 77 to 5 in mod 9.

Answer 6

yeah

Answer 7

i think its 1

Answer 8

it's not 1

Answer 9

its 5

Answer 10

correct