Commutative property of addition
A number line is infinite in both directions. When people say that addition is commutative, that means that it doesn't matter what order you add up the numbers. 3 + 6 [...]
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07, 2017
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07, 2017
Addition – How to add whole numbers
A number line is infinite in both directions. Adding numbers is like walking along a path, the number line. To add two small numbers, like 7 + 4, you can just [...]
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07, 2017
What are whole numbers? – Math
A number line is infinite in both directions. Whole numbers are the numbers you learned when you were first learning to count - one, two, three, four, five and so [...]
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07, 2017
Percents, fractions, and decimals
Each penny is 1% of a dollar. Percent comes from the Latin words "per cent". That means "out of a hundred," like there are 100 cents in a dollar. So [...]
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07, 2017
Which one is the numerator? Fractions
A pie cut into thirds The numerator of a fraction is the number on the top, just as the denominator is the number on the bottom. In the fraction 1/2, the numerator is one, and in [...]
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07, 2017
What are logarithms? Numbers and math
Earthquake in Peru - we measure earthquakes using logarithms What are logarithms? Logarithms are a way of writing numbers using exponents. "Log 100" means the exponent you'd need to use to get 100 [...]
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07, 2017
What is infinity? Math and numbers
Infinity: A number line is infinite in both directions. No end to the number line When we think about the number line, we can see that there's no end to it [...]
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07, 2017
Numbers and math
A number line is infinite in both directions. Numbers are a convenient way for people to organize their thoughts about space and time. First we can think of zero as a point, taking up no [...]
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07, 2017
What are fractions? – Math
A fraction of a pie: What are fractions? We started with whole numbers When we first thought about the number line, we counted only in whole numbers - we went straight from zero [...]
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07, 2017
What are factors? Factors and prime numbers
What are factors? Factors of a number: Three is a factor of nine. What are factors of a number? A factor is a whole number that fits evenly into another whole number. [...]
