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Math for Kids23 chapters | 325 lessons
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''Mom loves me best,'' Tony says.
''No way, I'm Mom's favorite,'' Sarah argues.
Have you ever had this argument with your brother or sister? Well, when you ask Mom, she'll say that she loves you both the same. You know that. The answer to how long will she love you is infinity!
There is a symbol that stands for infinity. Infinity means that something goes on forever. For example, numbers go on forever. You can add 1 to any number to get a higher number. Look at the symbol and follow it around and around with your finger. You never get to the end of it. It goes on forever, infinitely.
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Sometimes in math there are numbers that go on forever. Most of the time, they repeat the same numbers over and over again. For example, some solutions for division equations go on forever. They repeat, and continue to repeat, on and on and on.
Here's an example for you:
1 / 3 = 0.33333333333333333333333333333333333333333333333...
The 3s could go on forever. You could spend the rest of your life writing 3s and you still wouldn't reach the end. The 3s go on for infinity. It just doesn't make sense to spend the rest of your life writing 3s, so in math we would say 1 / 3 = 0.3 with a line over the three to show that the three repeats forever. This is called bar notation. Bar notation is an easier way to write a repeating number by putting a line, or bar, over the repeating numbers.
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Here's another example. 1 / 7 = 0.142857142857142857142857142857...
But using bar notation, you would say 1 / 7 = 0.142857 with a line over those numbers to show that they repeat over and over.
You can use the bar notation over any number that repeats the same number or numbers again after the decimal point. If I wanted to write the number 5.6788888888888 using bar notation, I would only put the bar above the first 8, because that is the number that is repeating forever.
You cannot use bar notation before a decimal point. Here's why. If you write the number 88, you can't put a bar over the 8 because that would mean the number 8888888888888888... See, it's a totally different number. Bar notation may only be used on a repeating number or series of numbers AFTER the decimal point.
Using bar notation, which is a way to show repeating numbers after a decimal point, is easier than writing the same repeating number and over again. It shows that the number pattern goes on for infinity, or forever. Bar notation can only be used after the decimal point.
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Math for Kids23 chapters | 325 lessons
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