Question Statement:
A drainage basin has 3 rain gauges $A, B,$ and $C$ with Thiessen weights of $0.25, 0.45,$ and $0.30$ respectively. If the storm rainfall recorded at gauges $A, B,$ and $C$ are $40\text{ mm}, 60\text{ mm},$ and $80\text{ mm}$ respectively, the average storm rainfall over the basin in $\text{mm}$ is ________ (answer in integer).