Since 2/3 of the 3/4 m high window is covered with frosted glass, multiply 2/3 by 3/4 to find what part of a meter is frosted glass:
[tex]\frac{2}{3}\times\frac{3}{4}=\frac{2\times3}{3\times4}=\frac{6}{12}=\frac{1}{2}[/tex]Therefore, 1/2 of a meter is frosted glass.