Question

Determine whether the congruence is true or false.
\(88\equiv 5\ mod\ 9\)

Answer 1

Calculation:
The congruence is \(18 \equiv 60\ mod\ 7\).
Consider \(\frac{18-60}{7}\),
\(\frac{18-60}{7} = -42/7 = -6\)
Because —6 is an integer, \(18 \equiv 60\ mod\ 7\) is a true congruence.
Hence, the congruence \(18 \equiv 60\ mod\ 7\) is true.