ations will have a solution. It's not difficult to derive the necessary and sufficient conditions for the existence of a solution. I will use the equations in (3) as an example. From the first equation we can write <span class="nowrap">N=R<sub>0</sub>+60m</span>, where m is an arbitrary integer. Substituting this expression into the middle equation in (3) gives</p><p>T(R<sub>0</sub>+60m)=R<sub>1</sub>+60An,</p><p></p><p>where n is an integer. This equation can be written as</p><p>60g<sub>1</sub>(mt-na)=R<su