If a learner is able to perform the four basic operations on whole numbers, fractions and decimal numbers, the learner is at :

If a learner is able to perform the four basic operations on whole numbers, fractions and decimal numbers, the learner is at : Correct Answer Operating phase

Mathematics is a branch of science which deals with counting, calculating, and studying numbers, shapes, and structures. The student learns the development the mathematics in the specified learning phases, through which the child gradually builds mathematical thinking.

Important Points

Operating Phase: In this phase, students can think of multiplications and divisions in terms of operators. A child is able to perform all number operations at this phase.

Key Points

Let's understand the 6 Phases of development in brief 

There is 6 Development Phase in Mathematics: The developmental phase of numbers plays a crucial role in learning mathematics because this starts with the basic mathematics patterns. The developmental phase of the number are explained in detail as follows:

1. Emergent Phase: Students come to understand that number words and symbols can be used to signify the “numerosity” of a collection. Recognize that numbers may be used to signify quantity.
2. Matching: students learn what people expect them to do in response to requests such as: How many are there? Can you give me six forks? How many are left? Which shows that they understand the numeric values or counting.
3. Quantifying: the significance of the number at the end of the counting process does not change with rearrangement of the collection or the counting strategy. They interpret small numbers as compositions of other numbers. Also, they develop the idea that constructing fair shares requires splitting the whole into equal parts without changing the total quantity and so begin to see the part-whole relations that link sharing and fractions. These students use part-part-whole relations for numerical quantities. Eg: 5+4 is always 9
4. Partitioning: students see that numbers have magnitudes about each other, can interpret any whole number is composed of two or more other numbers, and see the relationship between different types of addition and subtraction situations. Also, as a result, students see that numbers can be used to count groups and that they can use one group as a representative of other equal groups. These students use additive thinking to deal with many-to-one relations.
5. Factoring: Students see the significance of the connection between groups of ten or groups of one hundred and the way we write whole numbers. They can relate different types of multiplication and division situations involving whole numbers. They also link the ideas of repeating equal groups, splitting a quantity into equal parts, and fractions. These students think both additively and multiplicatively about numerical quantities Eg: i) if 3 rows of 5 are 15, then both 15 divided by 3, and one-third of 15 are 5, ii) Knowing without calculating, that 4 piles of 9 objects must be the same amount as 9 piles of 4 objects
6. Operating: Students see how the intervals between whole numbers can be split and re-split into increasingly smaller intervals and realize the significance of the relationship between successive places. For example, the value of each place is ten times the value of the place to its right and one-tenth of the value of the place to its left. Also, students learn to make multiplicative comparisons between numbers, deal with proportional situations, and integrate their ideas about common and decimal fractions. 

Thus, if a learner can perform the four basic operations on whole numbers, fractions, and decimal numbers, the learner is at the operating phase.