Choose the Correct Operation

What to do

In these problems, you must decide which operation fits the situation before you calculate. The key skill is matching the words and the meaning of the story to addition, subtraction, multiplication, or division.

A simple method

1. Read the whole problem first. Identify what is known and what is being asked.
2. Look for the action.
   • Add when amounts are combined or increased.
   • Subtract when something is taken away, compared, or there is a difference.
   • Multiply when equal groups, repeated amounts, or scaling are involved.
   • Divide when a total is shared equally or grouped into parts.
3. Write the equation. Use the operation that matches the situation.
4. Calculate carefully. If the result can be simplified, reduce it to its simplest form.

Check your choice

Ask yourself: Does my operation make sense in the story? If I reverse the operation, does it create a reasonable check? For example, if you added to find a total, subtracting the same amount should bring you back to the starting value.

Common mistake to avoid

Do not choose an operation just because of a keyword. Focus on the meaning of the situation, since words can sometimes be misleading.

Final check

Make sure your answer matches the question asked and is simplified if needed.