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Squaring Numbers
- beginning with 1
- beginning with 5
- beginning with 9
- ending in 1
- ending in 2
- ending in 3
- ending in 4
- ending in 5
- ending in 6
- ending in 7
- ending in 8
- ending in 9
- made up of 1's
- made up of 3's
- made up of 6's
- made up of 9's
- in the 20's
- in the 30's
- in the 40's
- in the 50's
- in the 60's
- in the 70's
- in the 80's
- in the 100's
- in the 200's
- in the 300's
- in the 400's
- in the 500's
- in the 600's
- in the 700's
- between 800-810
- in the 900's
- between 1000-1100
- between 2000-2099
- between 3000-3099
- between 4000-4099
- between 5000-5099
- between 6000-6099
- between 7000-7099
- 3's and final 1
- 3's and final 2
- 3's and final 4
- 3's and final 5
- 3's and final 6
- 3's and final 7
- 3's and final 8
- 3's and final 9
- 6's and final 1
- 6's and final 2
- 6's and final 3
- 6's and final 4
- 6's and final 5
- 6's and final 7
- 6's and final 8
- 6's and final 9
- 9's and final 1
- 9's and final 2
- 9's and final 3
- 9's and final 4
- 9's and final 5
- 9's and final 6
- 9's and final 7
- 9's and final 8
- 1 and repeating 3's
- 1 and repeating 6's
- 1 and repeating 9's
- 2 and repeating 3's
- 2 and repeating 6's
- 2 and repeating 9's
- 3 and repeating 6's
- 3 and repeating 9's
- 4 and repeating 3's
- 4 and repeating 6's
- 4 and repeating 9's
- 5 and repeating 3's
- 5 and repeating 6's
- 5 and repeating 9's
- 6 and repeating 3's
- 6 and repeating 9's
- 7 and repeating 3's
- 7 and repeating 6's
- 7 and repeating 9's
- 8 and repeating 3's
- 8 and repeating 9's
- 9 and repeating 3's
- 9 and repeating 6's
- 6-digits repeating
- 2 rep./sq. of 1 digit
Multiplying Numbers
Dividing Numbers
Adding Numbers
Subtracting Numbers
Finding Percents
Calculation
Practice Exercises
Full List
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Squaring numbers in the 900s
- Choose a number in the 900s - start out easy with numbers near 1000; then go
lower when expert.
- Subtract the number from 1000 to get the difference.
- The first three places will be the number minus the difference: X X X _ _ _.
- The last three places will be the square of the difference: _ _ _ X X X
(if 4 digits, add the first digit as carry).
Example:
- If the number to be squared is 985:
- Subtract 1000 - 985 = 15 (difference)
- Number - difference: 985 - 15 = 970: 9 7 0 _ _ _
- Square the difference: 15 × 15 = 225: _ _ _ 2 2 5
- So 985 × 985 = 970225.
See the pattern?
- If the number to be squared is 920:
- Subtract 1000 - 920 = 80 (difference)
- Number - difference: 920 - 80 = 840: 8 4 0 _ _ _
- Square the difference: 80 × 80 = 6400: _ _ _ 4 0 0
- Carry first digit when four digits: 8 4 6 _ _ _
- So 920 × 920 = 846400.
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