Question 39
In base $R_1$ the expanded fraction $F_1$ becomes $0.373737\ldots$ and the expanded fraction $F_2$ becomes $0.737373\ldots.$ In base $R_2$ fraction $F_1,$ when expanded, becomes $0.252525\ldots,$ while fraction $F_2$ becomes $0.525252\ldots.$ The sum of $R_1$ and $R_2,$ each written in base ten, is: