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## Class 2 math (India)

### Course: Class 2 math (India)>Unit 2

Lesson 5: Addition and subtraction using number line

# Adding and subtracting on number line word problems

Sal uses number lines to solve addition and subtraction word problems with numbers less than 100.

## Want to join the conversation?

• Is using a number line the best way to add and subtract? Because in some cases, it seems easier to not use a number line.
• Whatever is better for you. A number line is just a good illustration of what actually happens when adding or subtracting. As you go up, you won't need them at all (adding with them).
• if abcs work with numbers what is the number song?
• there isn't one, there is no stop to numbers, there are an infinite amount of numbers.
• . Why do I have to use a number line if I can quickly solve 30 + 4 + 3 + 2 to get 39?
• Using a number line makes addition easier for those who are weaker in that area
• How can I become a math genius who can do for example 583^2 in their head or something? They are born that way?
• Good question!

I often square numbers by using the property (a+b)^2 = a^2+2ab+b^2 (which follows from using the distributive property twice, or using an area model).

l would think of 583^2 as [600+(-17)]^2, which becomes
600^2+2*600*(-17)+(-17)^2
= 360,000-20,400+289
= 339,889.

• hi what is 63 + 27 on a number line
• We can use the addition trick of taking away 3 from the 63 and giving the 3 to the 27. This gives the easier addition problem 60 + 30. The answer is 90.
• what is 12,000000+12,000000
• 24,000000, or in word form, 24 million. Sorry for the late response by the way.
(1 vote)
• why can math be hard
when was math created
• Math is hard because it asks lots from our brains. Our human brains find other things easier, but things like painting or playing a violin are also hard. But if you practice they get easier.

Khan academy is the creation of Mr Khan :)

Some parts of math are already coded in your brain. Like knowing what is bigger or what is more. Putting math into "words" happened a long time ago. More than a 1,000 years!
• how is the numberline useful cause this is hard i get them wrong and get 40 30 20 14 0 for my grade :(
• In arithmetic, the number line is a useful way to visualize relationships among whole numbers, integers, fractions, and decimals, and to visualize operations performed on these types of numbers.

When you study algebra later on, you will need to be able to understand and construct graphs, on a number line and on a 2-dimensional coordinate plane (a combination of a horizontal number line for the x-axis and a vertical number line for the y-axis).

Later on in math, you will also need to be able to understand and construct graphical displays of data such as histograms, dot plots, box-and-whisker plots, bar graphs, line graphs, and scatterplots, which use number lines and/or coordinate planes.

Have a blessed, wonderful day!