If $$29^{}\text{th}$$May is Monday, what day of the week is $$1$$\textsuperscript{st~}May ? 
Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time
There are 29 days between $$29^{}\text{th}$$May and~ $$1$$\textsuperscript{st~}May.  Apart from $29$\textsuperscript{th} May itself, there are 28 days = 4 week.  Therefore,~~$$1$$\textsuperscript{st~}March is Monday. 