Question: how many centimeters are in the ruler?
Answer: 12 inches are 12 x 2.54 = 30.48 cm. Also means one foot or about 1/3 of a mètre. The hash marks on a standard 12 inch ruler demark inches so there are technically no centimeters on a standard 12 inch ruler. But 12 inches = 30.48 centimeters.