Decimals & Place Value
Each digit's value depends on its position: places left of the decimal point are ones, tens, hundreds; places right of it are tenths, hundredths, thousandths.
Converting between fractions and decimals is a core TEAS move: divide numerator by denominator to get a decimal, and read a terminating decimal as a fraction over a power of ten (0.45 is 45/100, which reduces to 9/20).