Place value becomes the denominator
One decimal place means tenths, two means hundredths, and three means thousandths. Write the digits over that place value, then reduce.
Turn a terminating decimal into a fraction and reduce it using the greatest common factor.
One decimal place means tenths, two means hundredths, and three means thousandths. Write the digits over that place value, then reduce.
Write 375/1000. The greatest common factor is 125. Divide top and bottom by 125 to get 3/8.