Math

RULES FOR COMPUTING WITH DECIMALS


Addition: When adding decimals...

  1. Write one number above the other, line up decimal points

  2. Bring decimal point down into answer line

  3. Fill in empty places with a zero

  4. Add numbers as usual



Subtraction: When subtracting decimals…

  1. Write greater number on top line.

  2. Write lesser number below and make sure decimal points are lined up; bring decimal point down into answer line.

  3. Fill in empty places with a zero

  4. Subtract numbers as usual



Multiplication: When multiplying decimals…

  1. Write longer number on top line.

  2. Write shorter number on lower line.

  3. Ignore decimal points and multiply as usual.

  4. Count digits on right side of decimal point in the factors, then move decimal point that many places to the left.



Division: When dividing decimals…

  1. Write numbers in a division “HOUSE”

  2. Move decimal point in the number on the outside over to the right to get rid of the decimal

  3. Move decimal point in the number inside the house the same number of places to the right

  4. Put the decimal up on top of the house

Now divide as usual