Unit 13

Multiplication of Decimal Fractions

Basic Principles of Multiplication of Decimal Fractions

• To multiply decimal fractions, multiply the numbers following the same rules for multiplication of whole numbers.

• Then count the number of decimal places to the right of the decimal point in both the multiplier and the multiplicand.

Basic Principles of Multiplication of Decimal Fractions

• Start at the far right number in the product and count off the same number of decimal places to the left before placing the decimal point. – If extra places are needed in the answer,

zeros are added on the left of the product before positioning the decimal point.

Multiplication of Decimal Fractions

• Example: Find the product:

27.5 x 3.42

– Multiply:

– Add the decimals and

place in the product.

Practical Problem

• A patient takes 0.625 milligrams (mg) of Premarin bid (twice a day) for 5 days.

• What is the total dose?

Practical Problem

• Multiply, then add the

decimals and place in

the product.

• The total dose is 6.25 mg.