SUBTRACTING MIXED NUMBERS
- WRITE THE PROBLEM SO YOU CAN SEE WHAT YOU’RE DOING
- Rewrite the problem.
- Move to STEP 2.
- THE SEPARATION OF PARTS – WHOLE NUMBERS FROM FRACTIONS
- Remove and write the whole numbers from the equation you wrote in STEP 1. Be sure to use the same operation.
- Subtract the whole numbers.
- Circle the difference in RED.
- Move to STEP 3.
- THE SEPARATION OF PARTS – FRACTIONS FROM WHOLE NUMBERS
- Remove and write the fractions from the equation you wrote in STEP 1. Be sure to use the same operation.
- If the denominators are commonand the subtraction IS POSSIBLE –
- Subtract the fractions and find the difference.
- Move to STEP 5
- If the denominators are common and the subtraction IS NOT POSSIBLE –
- Move to STEP 7
- If the denominators are NOT common and the subtraction IS NOT POSSIBLE –
- Move on to STEP 4
- FINDING A COMMON DENOMINATOR
- Use DUCKMAN to find the common denominator.
- If subtraction is possible, subtract the fractions and find the difference.
- Move to STEP 5
- If subtraction is NOT possible
- Move to STEP 7
- USING THE 2, 3, 5, 9, 10 RULES
- Write the fraction difference you got from STEP 3, STEP 4, or STEP 7
- Use the 2, 3, 5, 9, 10 rules to reduce and simplify the fraction to its lowest value.
- Be sure to use the same rule on the top and bottom. Never use two different rules.
- Continue to use the rules over and over until they no longer work.
- If the fraction is NOT an improper fraction, circle it in BLUE
- Move to STEP 8
- If the fraction IS AN IMPROPER FRACTION, move to STEP 6
- CONVERTING AN IMPROPER FRACTION TO A MIXED NUMBER
- Divide the numerator by the denominator
- Write the quotient as a mixed number and circle it in BLUE.
- Move on to STEP 8.
- STEALING TO MAKE SUBTRACTION POSSIBLE
- Write the subtraction problem that is not possible, being sure to start with a + in the front and leaving room to add a fraction in front of that.
- Go to the number in RED from STEP 2.
- Subtract 1 from that whole number, then write the NEW difference next to it and circle the new number in RED. Cross out the old whole number.
- Now, convert the 1 you stole and turn it into a fraction using the denominator that you need and write it in front of the + sign.
- Use the upside down pyramid to solve your new equation to get the difference.
- Circle it in BLUE.
- Move to STEP 5.
- GETTING YOUR ANSWER
- Write the answer you circled in RED from STEP 2.
- Write an addition sign.
- Write the answer you circled in BLUE from STEP 5 or STEP 6
- Add the RED to the BLUE to get the sum. (Be sure to add any whole numbers together first if you got a mixed number from STEP 5)
- Move to STEP 9.
- THE FINAL STEP
- Write the original problem again from STEP 1.
- Put an EQUAL sign.
- Write the answer you got from STEP 8. YOU’RE DONE!