Decimals are numbers that represent certain precise measurements that natural numbers cannot express. They consist of an integer part (on the left) and a decimal part (on the right), which are separated by a decimal point (,), e.g., 12,856. To the left of the decimal point, the digits are (as in natural numbers) in order: units (U), tens (T), … and to the right of the decimal point they are in order: tenths, hundredths, thousandths, … . The zeros at the end of the decimals have no value, e.g., 1,20 = 1,2. To convert a decimal fraction to a decimal number, we write the numerator and cut (separate) from the end with a decimal point as many decimal digits as there are zeros in the denominator. To convert a decimal number to a decimal fraction, we write the number in the numerator (without the decimal point) and the denominator as 10, 100, 1,000, …, depending on the number of decimal digits.