555:27

It looks like you're presenting a ratio or division problem (555 divided by 27). If that's the case, here’s the solution:

To calculate 555 divided by 27:

\[ 555 \div 27 \approx 20.5556 \]

So, the result is approximately 20.56 (to two decimal places). If you meant something else by "555:27," please provide additional context!