long division using fast facts. long division as fast facts eq: how can we divide large numbers into...
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Long Division Using Fast Facts
Long Division as Fast Facts
EQ: How can we divide LARGE numbers into groups using our
multiplication facts?
Take the example:
• Mrs. Parker wants to divide 565 new students into 5 new classes. Wow! What a lot of work to do… How can she divide this large number of children?
Start by making your FWA box: Facts, Work, and Answer!
Facts Work Answer
Facts Work Answer
Start listing all the 5 facts you can remember in your Facts box!
Facts Work Answer
Start listing all the 5 facts you can remember in your Facts box!
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Your work will go here; don’t forget to use your fast fact with zeros to help you get close without going over! Put your dividend at the top of this box.
565
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
What fast fact can you use to get as close to 565 as possible without going over?
565
565…
• I can use my fast fact 5 x 11 = 55 to get close to 565.
• I have to remember to get my hero (zero!) to help me out.
• 5 x 110= 550
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Take the fast fact you used + the zero! Place it in the answer box.
565 110 ( I used 5 x 11 = 55 plus my hero zero to get 5 x 110= 550)
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Come back to the work box and subtract 550. You used that much so far! What’s left?
565 -550 15
110
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Wow… I have 15 left.
What fast fact can I use?
565 -550 15
110
15…
• I can use my fast fact 5 x 3 = 15 to get to 15 exactly.
• I don’t have to remember to get my hero (zero!) to help me out because this is exactly 15
• 5 x 3= 15
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Take the fast fact you used. Place it in the answer box.
565 -550 15
110 3
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Come back to the work box and subtract 15. You used that much! What’s left?
565 -550 15 - 15 0
110 3
There is nothing left!Go back to your answer box and
add up all the fast facts (plus zero heroes) you used!
Facts Work Answer
5 x 1 = 5
5 x 3 = 15
5 x 6 = 30
5 x 7 = 35
5 x 9 = 45
5 x 10 = 50
5 x 11 = 55
Come back to the answer box. Add it all up! That’s your quotient.
565 -550 15 - 15 0
110+ 3
113
Phew! Mrs. Parker took care of her 565 new students. It looks like
each class will have….
Use your answer box...
110 + 3 = 113
There will be 113 students in each class.
Time to check our work!
• Use the inverse operation:
113 (students)
x 5 (classes)
565 (total student)
We are correct!