ARITHMETIC

Counting  Arithmetic  Fractions  Graphing  Algebra  Geometry


Operations:  Unit  Multi-digit

Exponents Squares Roots

Expressions


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Arithmetic

Arithmetic begins with Unit Operations. Students may select: Add, Subtract, Multiply or Divide, Choose to Include Negative Numbers, Freeze the Second Digit, and generate 1 5 or 10 questions at a time. There are 104 Unique operating modes. Scores track Attempts and Correct Answers for Each. An Activity Log matching the Score Page, may be printed from the Tools Help. It itemizes each operation and facilitates tracking and assessing student progress. A Number Line and Multiplication Table are examples intended to aid teaching and be a study reference while learning: Add, Subtract, Multiply and Divide.

Multi-digit Operations contains 4 tools and 4 examples. Examples animate the same way every time to aid teaching. Tools generate practice problems with detailed solutions each has an easier and harder operating mode.

Exponents Squares and Roots begins with a Graphic defining Base and Power and showing how to write it. Two Examples at the top illustrate Exponential Growth both Visually and Numerically. Tools at the Bottom require Estimating Radical Values and Simplification of Perfect Squares and Radicals with a Tutorial showing Prime Factorization.

The Expressions Section begins with an O-O-O Graphic, followed by 4 examples to be simplified by clicking through. The Make Expressions Activity has students combine digits with operations to make Target Numbers. Click a Target Number to display an Expression that uses Each Digit Once and Only Once.

Arithmetic Section Video

Properties and Operations

Simplify 4 Expressions

Below is a Numerical Expression meaning it simplifies to a single number   Click on it to simplify

(4 + (8 • 2²)) / ((2³ - 2) • 6)

(4 + (8 • 4)) / ((8 - 2) • 6)

(4 + 32) / (6 • 6)

36 / 36

1

Reset



Make Expressions Activity

Expressions Overview Video

Properties and Operations

Commutative
Distributive

Associative
Order of Operations


Addition accumulates Addends to produce a Sum

7 + 49 + 12 + 6 = 74 A d d e n d sSum

Addends are Commutative meaning they can be in any order and values can commute from one term to another

6 + 4 = 4 + 6   or   6 + 4 = 7 + 3



Subtraction takes away a Subtrahend from a Minuend producing a Difference

5  -  3 =  2Minuend   Subtrahend   Difference

Subtraction is NOT Commutative meaning order matters

Multiplication: Multipliers produce a Product

7 * 2 * 3 * 5 = 210 ← Multipliers →Product

Multipliers are Associative meaning terms can be in any order

6*4 = 4*6   or   A*B = B*A


Division: Divides a Dividend by a Divisor producing a Quotient and possibly a Remainder

5  ÷  2 =  2Dividend   Divisor   Quotient1 Remainder →

Division is NOT Associative meaning order matters

Distribution: is different for Addition and Multiplication

;'; Addition: 3 ( 5 + 2 ) = 3•5 + 3•2 = 21 Multiplication:3 ( 5 • 2 ) = 3•5•2 = 30


Click Expressions for Answers

2(2+3+5)=20
2(2•3•5)=60

9(1+1+1)=27
9(1•1•1)=9

5(2+0+5)=35
5(2•0•5)=0

3(2+3+5)=30
3(2•3•5)=90

reset

Order of Operations

First: ( ) Parenthesis

Second: ² Exponent

Third: * Multiplication / Division

Last: + Addition - Subtraction

   Equal Operations go from Left to Right →

First letter of operations in order are

PEMDAS

A common phrase to remember this order is

Please Excuse My Dear Aunt Sally



Reset

Print 4 Expressions

(4 + (8 • 2²)) / ((2³ - 2) • 6)

(4 + (8 • 4)) / ((8 - 2) • 6)

(4 + 32) / (6 • 6)

36 / 36

1


2³ • -3² / (16 + (1 - 3²))

8 • 9 / (16 + (1 - 9))

72 / (16 - 8)

72 / 8

9


10 + 5 • -2 + 20 - 4 • 5

10 - 10 + 20 - 20

0


10³ / 10² - 25

1000 / 100 - 25

10 - 25

-15

Addition accumulates Addends to produce a Sum

7 + 49 + 12 + 6 = 74 A d d e n d sSum

Addends are Commutative meaning they can be in any order and values can commute from one term to another

6 + 4 = 4 + 6   or   6 + 4 = 7 + 3



Subtraction takes away a Subtrahend from a Minuend producing a Difference

5  -  3 =  2Minuend   Subtrahend   Difference

Subtraction is NOT Commutative meaning order matters

Multiplication: Multipliers produce a Product

7 * 2 * 3 * 5 = 210 ← Multipliers →Product

Multipliers are Associative meaning terms can be in any order

6*4 = 4*6   or   A*B = B*A


Division: Divides a Dividend by a Divisor producing a Quotient and possibly a Remainder

5  ÷  2 =  2Dividend   Divisor   Quotient1 Remainder →

Division is NOT Associative meaning order matters

Addition Subtraction Multiplication Long Division
Example Example  Example  Example 


Online Tools: generate fresh content for practice, study and assessment. They keep track of attempts and correct answers in each mode.

Interactive Examples: show detailed operations and more, they are useful for teaching and study, replaying exactly the same every time.

Exponents have a Base and a Power

BP

BP = BBBBB... P times

103 = 10 • 10 • 10 = 1000

3 EXPONENTIAL EXAMPLES

Power of 10s Powers Cube 2N Activity


Estimate Radical Value

Simplify Square Roots



Squares and Square Roots are Inverses

Num² = Num

25  =  √  =  5

Review Perfect Squares thru 12


To Simplify Radicals Factor the Radicand
into Primes and Promote the Squares

75 = 5•5•3 = 5²•3 = 5√3

Prime Factorization

Perfect Squares: Radicands are randomly generated from:
4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144,
or any of the numbers above times 100.
In either case the answer is a perfect square.

Radicals: Generates a radicand from 5 prime numbers
either 2's, 3's, 5's, and possibly a 7 or an 11. Students
factor the number into primes removing perfect squares.


Attempt / Correct
Sq:0/0   Rad:0/0
resethide

Perfect Squares
Radicals
 NewAnswer

How to Simplify


Easy mode: generates a target number made from 3 prime numbers either 2s, 3s or 5s.

Hard mode: generates a target number made from 5 prime numbers either 2s, 3s or 5s and may include either a 7 or an 11.

Enter the prime factors in any order

Prime Factorization for

96 and 97

964822421226232131=stop2•2•2•2•2•3 = 96Prime Factors 9719797 is a Prime Numberthe only factors1 and 97Review Prime Numbersin Counting/Groups/ Multiples to 100

Attempt / Correct
E:0/0   H:0/0
 resethide

EasyHard
NewAnswer


Finding Factors of 2 3 5 Factorization of 96 97


Divisibility Rules for 2's 3's and 5's

If the number is even; 2 is a factor

If the number ends in 0 or 5; 5 is a factor

If the sum of digits is divisible by 3; 3 is a factor

This tool generates numbers up to 10000. Students click the line-segment where the square root lies

Students learn the Square and Root relationship between:

 10    20   30   40     50    60      70     80    90           100
100 400 900 1600 2500 3600 4900 6400 8100 and 10000.

Powers of Ten

121110 9876 5432 10 101,000,000,000,000:→ One Trillion 10100,000,000,000:→ One Hundred Billion 1010,000,000,000:→ Ten Billion 101,000,000,000:→ One Billion 10100,000,000:→ One Hundred Million 1010,000,000:→ Ten Million 101,000,000:→ One Million 10100,000:→ One Hundred Thousand 1010,000:→ Ten Thousand 101,000:→ One Thousand 10100:→ One Hundred 1010:→ Ten 101:→ One

Graph : Y = 2X for 1 Month

The X-axis is simple, each square is 1 and we need 30 squares.

The Y-axis is not so simple. We need a Logarithmic Scale where the bottom squares increase by 1 to be able to show the first few values and the top squares have units increasing by Millions.

We do not show such graphs in this program.

N is #Day : 2N = Pennies

1 = 21 = 1¢

2 = 22 = 4¢

3 = 23 = 8¢

4 = 24 = 16¢

5 = 25 = 32¢

6 = 26 = 64¢

7 = 27 = 128¢

8 = 28 = 256¢

9 = 29 = 512¢

10 = 210= 1024¢

11 = 211 = 2048¢

12 = 212 = 4096¢

13 = 213 = 8192¢

14 = 214 = 16384¢

15 = 215 = 32768¢

16 = 216 = 65536¢

17 = 217 = 131072¢

18 = 218 = 262144¢

19 = 219 = 524288¢

20 = 220 = 1048576¢

21 = 221 = 2097152¢

22 = 222 = 4194304¢

23 = 223 = 8388608¢

24 = 224 = 16777216¢

25 = 225 = 33554432¢

26 = 226 = 67108864¢

27 = 227 = 134217728¢

28 = 228 = 268435456¢

29 = 229 = 536870912¢

30 = 230 = 1073741824¢

Discuss How to Graph this Function

Save 1 Penny on Day 1, then 2 Pennies on Day 2, then keep doubling Pennies each day for one month?

#Pennies = 2n

Where n is the Day


21   =   2 ¢

22   =   4 ¢

23   =   8 ¢

24   = 16 ¢

25   = 32 ¢

- - - - - -

How many Pennies will you save on Day 30?

230 = 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 • 2 = 1073741824 Pennies = $10,737,418.24 → Over 10 Million Dollars.

Show Details

Attempt / Correct
0 / 0
reset hide

New Number

Example estimate: 3711

3711 is between 3600=60 and 4900=70 and

closer to 3600, click Line-Segment 60 to 65

01020304050607080 90100

Click the line-segment containing the value

Addition with re-Grouping 10s 21268+541First Add Ones → 8 + 4 = 12Next Add Tens → 1 + 6 + 5 = 12First Add OnesNext Add Tens3 ExamplesResetWrite the 2 in the ones column andCarry 1 to tens column as shown.Write the 12 Notice the 1 carriesover the the hundreds column.

771936478934754828479964+ 178+9537+678978972073228534AnswerAnswerAnswer1112322reset

2-Digit mode generates two 2-digit numbers to be added

4-Digit mode generates three 4-digit numbers to be added

NOTE: the answer field is different - the digits are entered in reverse order. See the Help Video.

  Attempt / Correct
2Dgt:0/0   4Dgt:0/0
hidereset

2-Digit   4-Digit
  NewAnswer


NOTE: the answer field tabs right to left so students may enter Sum as calculated. See an example in the Help Video.

Clear Input

Solution

Easy mode: Divisors are 2 or 10

Hard mode: Divisors are 3 through 9

Division is the Inverse of Multiplication.  If you have learned Multiplication Facts, Division Facts are the same Numbers re-arranged.  See examples below:

3 * 5 = 15  ←→  15 ÷ 3 = 5  ←→  15 ÷ 5 = 3

6 * 7 = 42  ←→  42 ÷ 7 = 6  ←→  42 ÷ 6 = 7

12 * 8 = 96  ←→  96 ÷ 8 = 12  ←→  96 ÷ 12 = 8

Long Division Example

Step-by-Step Solution

Full Solution

• 9 divides into 12 1 time Write 1 in Quotient • Multiply Quotient * Divisor, 9*1 Subtract from Dividend, • Process Next Digit(6) • 9 divides into 36, 4 times Write 4 in Quotient • Multiply Quotient * Divisor, 9*4=36 Subtract from Dividend • Process Next Digit (1) • 9 Does Not Divide Into 1 Show Final Answer We Can Keep Dividing... 9)1261 140 9 3 6 36 01 140 1/9

Show Solution

Answer: 140.1111111... repeating

Written as: 140.1

9)1261 140111 .. 10 910 910 000

Attempt/Correct
E:0/0   H:0/0
hide reset  

divisors
2,10    3 - 9
NEWANSWER


Use pencil and paper to solve
then enter answer

remainder


327513x 981 2 3270 1635003 1 167751+11 Ones Tens Hundreds Final Answer Reset


Multiply: 3 * 7 = 21, write the 1, carry 2

Multiply: 3 * 2 = 6, add 2, write 8

Multiply: 3 * 3 = 9, write 9

Multiply 1 by 327, shift partial product using a "0"

First, shift partial product 2 digits using a "00"

Multiply: 5 * 7 = 35, write 5, carry 3

Multiply: 5 * 2 = 10, add 3, write 3, carry 1

Multiply: 5 * 3 = 15, add 1, write 16

Add Partial Products to get Final Answer

Easier mode: generates a 2-digit number and a 1-digit number to be multiplied.

Harder mode: generates two 2-digit numbers to be multiplied.

Use Pencil and Paper to Copy and Solve Each Operation

Practice Often



Attempt / Correct
E:0/0   H:0/0
hide reset

  Easier Harder
NewAnswer

Solve Using Pencil and Paper
No Calculators Please

=


Easier mode: generates two 2-digit numbers to subtract.

Harder mode: generates two 4-digit numbers to subtract.


Start with Ones : Notice we cannot Subtract 6 from 5, so we re-group a 10, then Subtract 6 from 15 giving 9.

Subtract the Tens : Notice we cannot Subtract 9 from 7, so re-group 100, then subtract 9 from 17 giving 8.

Subtract Hundreds : 7 minus 6 equals 1.

9 8  1 885 -696 77 11


3 Examples

Reset


 

   Answer
    ones
tens-hundreds

 

   Answer
    ones
tens-hundreds

 

   Answer
    ones
tens-hundreds

    5  25  642 -387 3 5 1 1        5  11  710 -595 0 6 1 1        9  12  314 -185 0 2 1 1

reset

Attempt / Correct
2Dgt:0/0   4Dgt:0/0
hidereset

2-Digits   4-Digits
NewAnswer


The Answer Field is entered right to left ← ← so students may enter the answer as they calculate it. The Help Video shows an example.

Show Solution

You may:

• Select: Add, Subtract, Multiply or Divide

• Choose to include Negative Numbers

• Freeze Second Digits

• Generate 1, 5 or 10 Questions at a time

• View Scores Until the Window closes

• Use Number Line to explain, Add and Subtract

• Use Multiplication Table, to explain Patterns

Print Activity Log

Attempts/Corrects
NewAnswer
1510
  #questions

Add Sub Mult Divide
positive only include negatives
Freeze Second Digit
no 12 34 56 7
  8   9   10   11   12hide


How To
Add and SubtractMultiply and Divide


Multiplication Table

Number Line


Use numbers on each die to make a Target Number

Click a Target Number to display a solution.

(!) Factorial and more

Print Activity Sheet


 4 : (1 - 1) * 2 * 3 + 4

14 : 4 * 3 + 2 + 1 - 1

24 : 2 * 3 * 4 + 1 - 1

34 : 2³ * 4 + 1 + 1

44 : 4(3² + 1 + 1)

54 : 3²(4 + 1 + 1)

64 : 2 * 4(1 + 1)³

74 : 34 - (2 + 1)! - 1

84 : 34 + 2 + 1 * 1

94 : (4 + 1)! - (3 + 1)! - 2

Hide Expressions

New Roll



In this activity instructors may allow students to use the numbers more than once or not at all directly effecting the difficulty in making expressions. The expressions shown here, use each number exactly 1 time, to accomplish this for some target numbers a Factorial (!) Operation is used.

Factorial means multiplying down to 1, for Example:

3! = 3 * 2 * 1 = 6

4! = 4 * 3 * 2 * 1 = 24

5! = 5 * 4 * 3 * 2 * 1 = 120

Factorial is used in statistics to calculate probability and more. We do not discuss it further in this program.

Please extend this activity if you like! Roll your own dice and choose your own target numbers.

Use numbers on each die to make a Target Number

Click a Target Number to display a solution.

(!) Factorial and more

Print Activity Sheet


 7 : 5 + 2 + 2(3 - 3)

17 : 5 * 2 + 3! + (3 - 2)

27 : 5² + 2 + 3 - 3

37 : 2³ * 5 - (3! ÷ 2)

47 : 5 * 2(2 + 3) - 3

57 : (3! + 5)(2 + 3) + 2

67 : 5² * 3 - 2³

77 : (5 + 2)(2³ + 3)

87 : 3² * 5 * 2 -3

97 : 5²(3! - 2) - 3

Hide Expressions

New Roll



Show Groups Made
You made 0 groups

New Numbers


☺☺☺
make-10
count groups made



Multiplication thru 12x12

♦ Multiply by 0 and 1 ♦ Multiply by 10 ♦ *5 ends in 5 or 0 ♦ *2 Doubles Numbers ♦ *9 = *10 - *1 ♦ *11 = *10 + *1 ♦ *12 = *10 + *2 ♦ Squares: 5*5 = 5² ♦ Equivalence ♦ Learn them all 123456 789101112 123456 789101112 1234 5678 9101112 2468 10121416 18202224 36912 15182124 27303336 481216 20242832 36404448 5101520 25303540 45505560 6121824 30364248 54606672 7142128 35424956 63707784 8162432 40485664 72808896 9182736 45546372 819099108 10203040 50607080 90100110120 11223344 55667788 99110121132 12243648 60728496 108120132144

Any Number Times 0 = 0

Any Number Times 1 is the Same Number

Multiplying by 10 Adds a Zero to the Number

1•10=10;   2•10=20   3•10=30   4•10=40 . . .

Multiples of 5 End in 0 or 5, they are Half

of their Corresponding Multiple of 10

Multiplying by 2 Doubles the Number, Use

Halves and Doubles in Counting Section for Practice

Multiplying by 9 is like Multiplying by 10

then Subtracting the Number

Multiplying by 11 is like Multiplying by 10

then Adding the Number

Multiplying by 12 is like Multiplying by 10

then Adding the Number Doubled

A Number Multiplied by Itself it is called Squared

1•1=1²   2•2=2²   3•3=3² . . . X•X=X²

Multiplication is Associative meaning is is the same forward of backwards. Half the table is the same!

Say them!   Write them!   Learn them!

Number Line

Unit Operations


-5 to 5-50 to 50-500 to 500

⇐ Subtraction (-)(+) Addition ⇒ -1-2-3-4-5012345 -5 - 5 = -10 where to start ⇒ direction to move how many to move Answer -10-20-30-40-5001020304050 -50 - 50 = -100 where to start ⇒ direction to move how many to move Answer -100-200-300-400-5000100200300400500 -500 - 500 = -1000 where to start ⇒ direction to move how many to move Answer

Multiplication Table

Unit Operations

Any Number to the 0 Power = 1 Any Number to First Power = Same Number 10 to the 2 Power = 10 • 10 10 to the 3 Power = 10 • 10 • 10 100101 10 2103 Discuss 10   Power ? 4