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Squaring Numbers
Multiplying Numbers
Dividing Numbers
Adding Numbers
- even numbers 2 through selected 2-digit evens
- digits of square of repeating ones
- consecutive odds
- consecutive between 2 numbers
- sequence from 1 to selected 2-digit number
- sequence from 1 to selected 1-digit number and back
- sequences in the 10's
- sequences in the 20's
- sequences in the 30's
- sequences in the 40's
- sequences in the 50's
- sequences in the 60's
- sequences in the 70's
- sequences in the 80's
- series of doubles
- series of quadruples
- series of 10 numbers
Subtracting Numbers
- 1's repeating, divide by 9, subtract 21
- 8's repeating, divide by 9, subtract 10
- squares of two numbers
- reversing/adding/subtracting 3-digit numbers
Percents
- finding 2.5 percent
- finding 5 percent
- finding 15 percent
- finding 20 percent
- finding 25 percent
- finding 33 1/3 percent
- finding 40 percent
- finding 45 percent
- finding 55 percent
- finding 60 percent
- finding 70 percent
- finding 75 percent
Calculation
Practice Exercises
Full List
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Add a sequence from one to a selected
1-digit
number and back
- Choose a 1-digit number.
- Square it.
Example:
- If the 1-digit number selected is 7:
- To add 1 + 2 + 3 + 4 + 5 + 6 + 7 + 6 + 5 + 4 + 3 + 2 + 1
- Square 7: 49
- So the sum of all numbers from 1 through 7 and back is 49.
See the pattern?
- If the 1-digit number selected is 9:
- To add 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1
- Square 9: 81
- So the sum of all numbers from 1 through 9 and back is 81.
You will certainly be faster with your answer than someone
adding all the numbers up on a calculator!
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BEATCALC: Beat
the Calculator!
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