Find here many important 4th grade math concepts taught in 4th grade. Teachers, parents, and math tutors can also use them as a guideline to illustrate a math lesson or to teach important skills that kids are supposed to know in 4th grade math.

**Decimal notation for fractions**

**Ray**

A ray has one endpoint where it starts and it extends forever on the other side.

**Add mixed numbers**

**Read whole numbers**

Which number can be read as six thousand, four hundred eighty-seven?

A. 64087 B. 6087

C. 6487 D. 8764

**Proper fraction**

Numerator is smaller than denominator**Improper fraction**

Numerator is bigger than denominator.

**Right triangle**

A right triangle has one right angle.

**Benchmark fractions in 4th grade math**

Fractions that are used frequently to do estimation.

**Congruent shapes**Shapes are congruent when they have the same shape and size.

**Common denominator**

Multiples of 3 are 3, 6, 9, 12, 15, ...

Multiples of 4 are 4, 8, 12,16, ...

Common denominator is least common multiple or 12.

** Subtraction algorithm**

4 5 6

- 3 9 8

____________

4 16

4 5 6

- 3 9 8

___________

8

3 1 4 16

4 5 6

- 3 9 8

__________

0 5 8

** Subtraction algorithm**

4 5 6

- 3 9 8

________________

4 16

4 5 6

- 3 9 8

________________

8

3 1 4 16

4 5 6

- 3 9 8

________________

0 5 8

**Line of symmetry**

**Arc**

An arc is a part of a circle. The arc is shown in orange.

**Algorithm for multiplication**

**Measure of an angle**

The angle on the right measures 150 degrees

150 degrees

**Equation**

A mathematical sentence with an equal sign. The equal sign separates the left side from the right side. The amount on the left side of the equation is always equal to the amount on the right side.

4 + 6 = 10

1 + 12 = 13

20 = 9 + 11

**Equation**

A mathematical
sentence with an equal sign. The equal sign separates the left side from
the right side. The amount on the left side of the equation is always
equal to the amount on the right side.

4 + 6 = 10

1 + 12 = 13

20 = 9 + 11

**Tenth and hundredth**Tenth: one of the equal parts when a whole is divided into 10 equal parts.

Hundredth: one of the equal parts when a whole is divided into 100 equal parts.

**Hundredths**

The hundredths place is shown in red. The 9 means that 9 parts are colored out of 100.

8.29

**Intersecting lines**

**Comparing decimals**

Put the following decimal in order from greatest to least.

4.23 4.24 4.2 4.30 4.19

**Answer:**

4.30 4.24 4.23 4.20 4.19

**Mixed number**

A mixed number has 2 parts. First it has a whole number that is 2. Second, it has a fraction that is 4/5.

**Formulas**

Area and perimeter of a rectangle

Area = length x width

Perimeter = 2 x length + 2 x width

**Circle**In a circle, you can put points anywhere on the purple arc. These points will be at the same distance from the fixed black point called center.

**Tenths**

The tenths place is shown in red. The 2 means that 2 parts are colored out of 10.

8.29

**Composite number**

A number with more

than 2 factors. Factors

of 8 are 1, 2, 4, and 8.

8 is a composite number

since it has 4 factors

or 4 numbers than

can divide it evenly.

12, 9 and 8 are composite numbers.

**Factor pairs**A factor pair refers to

a set of two numbers

when multiplied will

yield a specific product.

Factor pairs of 12

are (1,12), (2, 6),

and (3, 4)

**Obtuse angle**An angle bigger than 90 degrees

**Decimal**

10.50 5.25 61.0 0.40 .333

**Number line**

A straight line on which we put 0 and counting numbers.

**Reasonableness**

There is no need to

do the math. Instead

use estimation to

eliminate answers that

are unreasonable.

50 times 30 = 1500,

therefore, the answer is 1551

What is the product

of 47 times 32?

A. 4514 B. 1551

C. 2947 D. 8114

**Multiplicative comparison**

Peter has 5 times 4 = 20. Together they have 20 + 4 = 24

John has 4 tennis ball.

Peter has 5 times as many tennis ball as John.

How many tennis ball do they have together?

**Perimeter**

Perimeter = 2 x length + 2 x width

= 2 x 6 + 2 x 2

= 12 + 4

= 16

Area = 6 x 2 = 12

**Solve an equation**

What is the value

of b in the equation

below?

5 + b = 12

Since 5 + 7 = 12,

b = 7

**1 ounce**

A slice of bread

A CD without the case

2 or 3 strawberries depends on the size

**Pattern:**

What is the next

number in the list?

12 15 18

**Decompose a fraction**

3/5 = 1/5 + 1/5 + 1/5

**Example of prime numbers**

A prime number is a number

that has only 2 factors, 1

and the number itself.

7 is a prime number because

only 1 and 7 can be

multiplied to get 7

5, 7, and 13

**Decimal point**

The decimal point is the dot (.) separating the whole number from the fraction in the decimal notation.

**Equivalent fractions**

**Order of operations**

3 + (2 + 4) x 5

Do parenthesis

3 + 8 x 5

Do multiplication

3 + 40

Add

43

**1.** Make sure that students understand most of the math skills above taught in 4th grade math. If you would like to measure their understanding of math skills taught in 4th grade math, please check this 4th grade math test.

**2.** These 4th grade math concepts are in line with 4th grade math common core state standards.