Inverse

modular inverse of 27 modulo 29 = 14

27 mod 29 = 27

[14 * 27] mod 29 = 1 

Thanks guest.

14 is correct.  I think guest did it with a calculator.

This is fine but I will give a non-calculator answer

Find N such that  27*N (mod29) = 1

$27\equiv-2 \mod 29\\ 30\equiv 1 \mod 29\\ -2*-15 = 30 \equiv 1 \mod29\\ -15\equiv 29-15 \mod29 \equiv 14 \mod29\\ so\\ 27*14=1 \mod29\\ \text{So 14 is the modular inverse of 27 (mod 29)}$