A 30-centimeter ruler is about as long as a one-foot ruler. One centimetre equals 0.0328083989501 feet; therefore, thirty centimetres equals 0.9842511968504 feet. The converted distance can be rounded to the nearest foot.
The centimetre is a standard SI (International System of Units) measurement. One centimetre equals ten millimetres or one-hundredth of a metre. One centimetre is equal to 0.393700787402 inches when converted to inches; hence, 30 centimetres is equal to 11.811023622 inches, or 12 inches when rounded to the nearest whole number. One foot is equivalent to 12 inches. The standard ruler used in classrooms is marked with 12 inches on one side and 30 cm on the other.