



 
Hi Joyce, One hectare is 10,000 square meters and 1 millimeter is $\large \frac{1}{1000}$ meters so 5 mm of rain on one hectare produces a volume of \[10,000 \times \frac{5}{1000} = 50 \mbox{ cubic meters.}\] How much does 1 cubic meter of water weigh? Ask Google. Penny  


Math Central is supported by the University of Regina and the Imperial Oil Foundation. 