A number line is a way of representing numbers and their relationship in visual form on a straight line. The numbers are placed on this line at equal distances. The middle point is marked at ‘zero’ value and the rest numbers are placed on both sides of it on this line. The value of numbers increases towards the right side of a number line, and the value of the numbers decreases towards the left side of the number line. The numbers listed on the right side of zero are positive and those on the left side of zero are negative numbers.
It becomes easy to compare the numbers when put on a number line. It also helps to make calculations conveniently. A number line contains three parts starting from left to right. These are the negative part, zero, and positive part. On a number line, the numbers on the left are always smaller than the numbers on their right. For example, 2 is placed to the left of 5, so we can say 2 < 5. Again -4 is placed to the left of -1, so we can say -4< -1.
We can represent various types of numbers on a number line, such as whole numbers, integers, fractions, decimals, rational numbers, etc.
Drawing a Number Line
To place a number on a number line, the steps to be followed are as below:
- A horizontal line is drawn as a number line.
- Select an interval for the distribution of numbers. For plotting small numbers, choose smaller or closer intervals, and for plotting large numbers choose a larger interval.
- Mark the points on the number line according to the chosen interval.
- Mark zero value at the middle point and pace numbers on both sides of it according to intervals.
- Starting from zero, place positive numbers on the right side and negative numbers on the left side.
Let’s Learn Number Names
A number name is an expression of a numerical quantity or value in words. For example, the numbers 1, 2, 5, 11 can be written in words like one, two, five, and eleven. The basic number names like one to ten also help us to write numbers of higher values in words. After eleven and twelve, for the numbers 13 to 19, a pattern is followed (the number + teen). Thus the numbers are read in words as thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, and nineteen. After the number twenty, for 21 to 29, again a pattern is followed and the numbers are written by adding one, two, three, and so on after twenty. After thirty, that same pattern for number names is followed. Only different number names are applicable for forty, fifty, sixty, etc. which are multiples of ten.
There is a very easy and interesting concept that can help you remember the number names according to numbers.
For example,
- 147 = 100 + 40 + 7 = One Hundred + forty + seven
- 2563 = 2000 + 500 + 60 + 3 = Two thousand + five hundred + sixty + three
There are different forms of giving names to numbers based on the place value or position of the digits. As per the International system, while writing a large number, segments are formed by placing a comma after the hundreds place and then placed after every three digits. This helps to read and write large numbers easily. For example, the number 19,372,586 in the International system will be written in words as nineteen million three hundred seventy-two thousand five hundred eighty-six. As per the Indian system, the same number is written in words as one crore ninety-three lakhs seventy-two thousand five hundred and eighty-six. Learn this concept in an interesting way from Cuemath.
