Rumus Matematika SD, Lengkap dengan Penjelasannya

The following elementary math formulas can help students who are still in elementary school to work on various math problems.

Learning Mathematics is very important, because it is useful for everyday life. By learning Mathematics, we are trained to solve problems and think rationally.

So, it is important to understand the existing Math problems. Every matter of course always requires a calculation formula. The following is a collection of elementary Mathematics formulas that you can learn:

Complete Elementary Mathematics Formula

The summary of the Elementary Mathematics formulas below covers Mathematics lessons from grades 1 to 6 of elementary school.

1. Set of Numbers

Natural numbers = {1, 2, 3, …}
Whole Numbers = {0, 1, 2, 3, …}
Integer = {…, -3, -2. -1, 0, 1, 2, 3, …}
A rational number = a/b, where a is an integer and b is a natural number. a is called the numerator and b is called the denominator.

2. The nature of working with whole numbers

Commutative property (exchange)
a + b = b + a
a x b = b x a
Associative properties (grouping)
(a + b) + c = a + (b + c)
(a x b) x c = a x (b x c)
The property of adding zero
a + 0 = 0
The multiplication property of the number one
a x 1 =a
Distributive nature (spread)
a x (b + c) = (a x b) + (a x c)

3. How to Work Fractions

Adding two fractions with the same denominator
a/b + c/b = (a + c)/b
Subtracting fractions with the same denominator
a/b – c/b = (a – b)/c
Multiplication of fractions
c x a/b = (c x a)/b
(a/b) x (c/d) = (a x c)/(b x d)
(a/b) x (b/a) =1
Fraction division
c : (a/b) = c x (b/a)
(a/b) : c = (a/b) x (1/c)
(a/b) : (c/d) = (a/b) x (d/c)
Mixed fraction
A(b/c) = ((A x c) + b/c

4. Properties of Working Whole Numbers

Commutative property (exchange)
(a/b) + (c/d) = (c/d) + (a/b)
(a/b) x (c/d) = (c/d) x (a/b)
Associative properties (grouping)
((a/b) + (c/d)) + (e/f) = (a/b) + ((c/d) + (e/f))
((a/b) x (c/d)) x (e/f) = (a/b) x ((c/d) x (e/f))
The nature of the number zero
When all fractional numbers are added to zero, the result is the fraction itself: (a/b) + 0 = (a/b)
When all fractional numbers are multiplied by zero, the result is zero: (a/b) x 0 = 0
The nature of the number one
When all fractional numbers are multiplied by one, the result is the fraction itself: (a/b) x 1 = (a/b)
Opposite nature
All fractional numbers when multiplied by their reciprocal give one: (a/b) x (b/a) = 1
The nature of the spread
(a/b) x ((c/d) + (e/f)) = ((a/b) x (c/d)) + (a/b) x (e/f))

5. Wake up flat

Perimeter = (2 x length) + (2 x width)
Area = length x width
Perimeter = 4 x side
Area = side x side
Perimeter = side + side + side
Area = 1/2 x base x height
Perimeter = (2 x a) + (2 x b)
Area = base x height
Perimeter = a + b + c + d
Area = 1/2 x number of parallel sides x height
Perimeter = x diameter or 2 x x radius
Area = x radius x radius; where is equal to 22/7 or 3.14
Perimeter = (1/2 x x diameter) + diameter or (π x radius ) + 2 x radius
Area = 1/2 x x radius x radius
Quarter circle
Perimeter = (1/2 x x radius) + 2 x radius
Area = 1/4 x x radius x radius

6. Build Space

Volume of a rectangular prism or block = length x width x height
Volume of cube = side x side x side
Volume of triangular prism = 1/2 x length x width x height
Volume of cylinder = x radius x radius x height
Volume of cone = 1/3 x x radius x radius x height

7. Unit of Length

For every step up one ladder, the unit of length is multiplied by 10. Meanwhile, for each step of a ladder, the unit of length is divided by 10.
The equation of all the stairs above becomes as follows:

1 meter (m) = 0.001 kilometers (km)
1 meter (m) = 0.01 hectometer (hm)
1 meter (m) = 0.1 dekameter (dam)
1 meter (m) = 10 decimeters (dm)
1 meter (m) = 100 centimeters (cm)
1 meter (m) = 1000 millimeters (mm)

8. Unit of Time

1 century = 100 years
1 windu = 8 years
1 lustrum = 5 years
1 month = 28 days or 29 days or 30 days or 31 days
1 week = 7 days
1 year = 365 days (common year) or 365 days (leap year)
1 day = 24 hours
1 hour = 60 minutes
1 minute = 60 seconds

9. Explaining Data

The mode is the value that occurs most often
The median is the middle value
The mean is the average: the sum of all data/number of data

Those are various elementary math formulas that can help you to do the questions. The more you practice math problems, the more you will understand them.

This Snail is Smaller Than Sand

The research team from the Eötvös Loránd Research Network in Hungary found the world’s smallest species of snail. The height of the shell is only about 0.48 millimeters. With a volume of 0.036 cubic millimeters, it takes 5 of these snails to match the average size of a grain of sand.

The new species, named Angustopila psammonion, was found in soil sediments in a cave in Quang Ninh province, Vietnam.

Angustopila psammonion broke the record for the smallest snail previously held by Angustopila pallgergelyi which was discovered in 2014 in Thailand.

To find this snail shell, researchers took a sample of cave soil, put it in a container filled with water, and cleaned up floating debris. Then the soil sample is dried, then examined through a microscope.

Researchers believe that this species did not live in caves, but came from the forest and was dragged into the cave where it was later found by researchers.

“We assumed that the sediment [containing this snail] had entered through the cave crevices, because [these snails] have gastropod shells [typical among surface-dwelling terrestrial snails and [have undergone] bleaching. These snails may live deep in limestone crevices or close to the root system of [trees].” said

– Páll-Gergely, one of the researchers who discovered this new species of snail –

In another study, a team also led by Páll-Gergely found micro-snails—but not the smallest snails—from the Bolikhamsai province, Laos and have very unique characteristics.


Angustopila coprologos, the name of the species, has a grainy texture that decorates its shell. Uniquely, these granules are made apart from a separate structure from the shell. Researchers believe these granules are made of mud, or may also come from snail droppings.

“This Laotian species is interesting because during its lifetime it has deposited mud grains (which may have been their own feces), like small mosaic stones, with a clear pattern of radial and regularly spaced lines on the surface,” the researchers wrote in a research paper published in Contribution to Zoology. early 2022.

Páll-Gergely added, this small size has advantages such as being able to reach rock crevices that its competitors cannot reach.

In addition, the very small size makes these species increasingly difficult to be seen or hunted by predators.

Elderberry Benefits for Health

We all want a healthy body with a strong immune. That way, the body is not susceptible to viruses or diseases. Consumption of fruits that are rich in vitamins and antioxidants can be one way to maintain a healthy body.

Elderberry, a fruit that looks like a grape with a small size has many benefits for the body. One cup (145 grams) of elderberry fruit contains 106 calories, 26.7 grams of carbohydrates, 52.2 milligrams of vitamin C, 0.7 grams of fat, and 1 gram of protein. Not only that, this tiny fruit is also very rich in antioxidants.

Elderberry Benefits for the Body

Unfortunately, not many people know and are interested in elderberry. In fact, the content in this fruit has a myriad of benefits for the health of the body. Anything?

1. Reduces Inflammation

Two ingredients in elderberry—anthocyanins and nitric oxide—can slow pain and swelling such as bruises, toothaches, and burns.

According to a scientist-doctor at Rush Medical College, Chicago, elderberry contains bioactive compounds, namely tannins and flavonoids, which are anti-inflammatory compounds. Both of these ingredients can also prevent damage to body cells.

This cell damage will cause new problems, namely free radicals that are harmful to the body because they can cause various chronic diseases. For example, heart disease, Alzheimer’s, and cancer.

2. Healthy Digestive System

Each cup of elderberry contains 10.2 grams of fiber which can keep the good bacteria in the gut in balance. That way, the body can avoid various digestive problems such as constipation, diarrhea, and hemorrhoids.

3. Relieve Flu Symptoms

In 2016, scientists in Australia examined the health benefits of elderberry. As a result, they found that elderberry could reduce the risk of getting the flu. In 2019, it was also discovered that black elderberry can smooth the upper airway which can help relieve colds and flu.

4. Maintain Body Endurance

The fruit, flowers, and leaves of elderberries are excellent sources of antioxidants. In fact, the anthocyanin content in this fruit has an antioxidant power 3.5 times stronger than vitamin E.
With the content of vitamins and antioxidants along with the consumption of nutritious foods, elderberry consumption can help the body stay strong and can fight viral infections effectively.

5. Maintain Heart Health

The flavonoid content of elderberry can provide various benefits, such as lowering cholesterol and blood fat levels, and reducing the risk of heart disease in a person’s body. Other studies have also shown that this fruit can keep blood sugar normal.

Regularly consuming elderberry in sufficient quantities can provide benefits for the body. The good effects that elderberry gives to the body can be obtained in a concise and easy way, one of which is by taking daily supplements such as Ammunizer.