Homework Help for 4th Grade Math Students

Help with 4th Grade Math

Factors

Factors are the numbers you can multiply together to get a product. For instance, one and two are factors of two because 1 x 2 = 2. The number 12 has one, two, three, four, six and 12 as its factors, since 1 x 12 = 12, 2 x 6 = 12 and 3 x 4 = 12.

Multiples

You can think of multiples as the opposite, or inverse, of factors. A number's multiples are all of the numbers that are divisible by it. To find a number's multiples, just multiply it by each whole number, starting with one. For example, the first few multiples of three are three, six, nine and 12, since 1 x 3 = 3, 2 x 3 = 6, 3 x 3 = 9 and 4 x 3 = 12.

Metric Measurement

The metric system of measurement is another key 4th grade math concept. The basic units for measuring length are meters (m). For smaller items, you can use centimeters (cm), which are equal to 1/100 of a meter. Kilometers, which are used to measure longer distances, are equal to 1,000 meters.

The main unit for measuring mass is the gram (g), but kilograms (kg) are used for heavier items. One kilogram is equal to 1,000 grams.

You can use these equivalencies to convert between different units of measure. For instance, since one kilometer equals 1,000 meters, four kilometers equals 4,000 meters. Likewise, 3,000 grams equals three kilograms, since 1,000 grams equals one kilogram.

Classifying Shapes

In 4th grade geometry, you'll classify shapes based on two important characteristics: right angles and parallel lines. Right angles are angles formed by two perpendicular lines, and they measure 90 degrees. Two lines are parallel if they are the same distance apart at every point.

You'll classify a 4-sided shape as a trapezoid if it has two parallel sides and no right angles. If a shape has two sets of parallel sides and four right angles, then it's a rectangle. A 4-sided shape with two sets of parallel sides and no right angles is a parallelogram, and a triangle that includes a right angle is a right triangle.

Symmetry

You'll also learn about lines of symmetry in 4th grade math. These lines divide a shape into two identical parts. Some shapes, like squares, have many lines of symmetry. Others, like trapezoids, only have one line of symmetry. Parallelograms are an example of a shape with no lines of symmetry.