Ollowing radiogenic U-Pb values were determined from a monazite in Puruvesi leucogranite (Kurhila et al. 2011):206Pb/ 238U= 0.32134; 207Pb/235U= 4.8875; 207Pb/206Pb=0.11031. Determine the ages corresponding to the three isotope ratios.

I want to know how should i solve this with given ratios and there is something related to interpolation from the given tables.