Before we dive right into addition using a number line, let me tell you a story.
Once there was a boy, Rahul who loved to watch football. One day he went to see a football match with his parents. Before the match started he saw a very interesting thing in the field, the players were standing one after another maintaining equal gaps in between them. Suddenly he noticed that the jerseys they were wearing all had numbers in the back and the players were standing according to their jersey numbers starting right from zero to nine. Seeing this Rahul was really fascinated. Even after the match ended he could not forget that. So he decided to ask his mother about it, and his mother replied that they all were standing like a number line.
What is Number Line?
So what is a number line? A number line is nothing but a line where all numbers starting from zero are placed one after another without skipping any number and maintaining an equal gap between two numbers, just like the players were standing on the football field. The numbers placed in the number line increase as we move from left to right and decrease as we move from right to left.
A number line can also be used to represent negative numbers; negative numbers are the numbers that we will get if we keep on moving to the left from zero.
How can we make a number line?
Making a number line is easy. First, we need to make a line. Then comes the number, where the numbers should be placed? They need certain marks to be placed. So now we will make the marks using a ruler. Keeping the zero of the ruler on the line we will make a mark, measure the length of the gap between the zero and the mark you just made. Then keep the zero on the mark and make another mark keeping the gap the same as the previous. Likewise, make a few more marks on the line. Now number each of the mark starting from zero gradually increases as we move to the right. And that is how we draw a number line.
Why do we need number lines?
Writing numbers on a number line make comparing two numbers effortless. Numbers appearing on the left are always smaller than the numbers on the right on the number line. Knowing how to use a number line can prove to be very handy when carrying out arithmetic operations like addition, subtraction and multiplication. We always move right to add and move left to subtract two numbers.
How to Add Using Number Line
Let’s consider a situation, someone gives you 2 chocolates and you had 3 of those already. So how many total chocolates do you have now? To know the total number of chocolates, you will count, right? You will put together those two chocolates which were given to you along with the ones you already had. But what if you were asked the same question but this time you were told to add three with two. And here comes the role of the number line. This putting together is called addition and the number line makes this putting together a very easy task.
Let us take another example, let’s say you were asked to add 4 with 2. To add these numbers using the number line, you need to first locate the number 4 in the number line. Once you located the number 4, you need to hop 2 times or two-unit places to the right. The number you get is the sum of 4 and 2 that is 6. Hopping means jumping to the next place in the number line. And you need to always jump to the right to add the numbers. You can’t jump left from the number, which will give us the wrong answer for addition.
Let’s take another situation, say you were given a number line up to nine and you were asked to add 7 and 3. You will first locate seven in the number line and hop three-unit places to the right to add these numbers but you see you can hop only two times. In these cases, if you can’t hop the required number of times you can always increase the length of the number line.
These were a few examples describing how you need to use number lines to add two numbers. Now you need to practice the worksheet given below to get a tighter grip on number lines.
Number lines & Equations Printable Worksheets for Grade 1
Hope you liked these number lines & equations printable worksheets for grade 1. Please check our collection of math printables for grade 1.
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