Three small children in yellow shirts and one in a red shirt are rollerblading on a shiny marble courtyard .
There is a very good chance that four children are rollerblading in their grandfather 's courtyard .
It is unlikely that four children are rollerblading in their grandfather 's courtyard .
There is a very good chance that four children are rollerblading in their grandfather 's courtyard .
Four children are rollerblading in their grandfather 's courtyard .