modular arithmetic - Find $a$ inverse modulo 30, $1le a le 30$. For each $a$ you find, find the inverse of each $a$ that have inverse modulo 30

Find $a$ inverse modulo 30, $1\le a \le 30$. For each a you find, find the inverse of each a that have inverse modulo 30

a={1,7,11,13,17,19,23,29}

They got a by the fact that relative primes are inverses. I was wondering if this rule also applied if $a \ge 30$?

Find the inverse of each of the integers in a that have an inverse modulo 30

Not really sure how to do this part