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There's a lot of zeros in that chart. How do you help your children comprehend big numbers? Start with something they understand and then build on it. It's easy to understand 100 using 100 pennies. If you had enough pennies to make ten dollars, you'd have 1000 pennies. If you had enough pennies to make 100 dollars, you'd have 10,000 pennies. Get ten dollars worth of pennies to use as a visual of just how big a pile 1000 pennies would be. Find a container that will hold 1000 pennies. If you had ten containers, you'd have 10,000 pennies. If you had 100 containers, you'd have 100,000 pennies. If you had 1000 containers, you'd have 1,000,000 or 1 million pennies.

If you own a set of Cuisenaire rods, you can use the 1x1 centimeter rods as a visual aid for large numbers. If you built a ten centimeter cube using one rods you would use 100 rods. Follow the chart below to continue on to really big numbers.

Writing Big Numbers: Or What to Do With All Those Zeros

In the chart above, scientific notation was given for each of the big numbers used. It's a mathematical shortcut that makes using big numbers much easier. Usually, you will see scientific numbers written like the image to the right. There are two parts to a number written in scientific notation. The first part is called the coefficient. The second part is called the base and is usually written as an exponent. Another online standard way of show an exponent is to use the ^ (caret) symbol to show that the next number is the exponent. We're using the ^ symbol on this page.

The chart below shows some possible values for the base.

10 = 10^1
100 = 10^2
1000 = 10^3
10,000 = 10^4
100,000 = 10^5

It's easy to transform any number that starts with one and all zeros after that. Take the the two digits that are furthest left in the number. Count the number of zeros going right to left in the number. If your number is 10,000, 1 and 0, or 10, are the two digits furthest left. There are 4 zeros. 10,000 in scientific notation is 10^4. We leave out the coefficient because it is 1. Any number times one is that same number. So we don't need to say 1 X 10^4.

Take the following steps to turn other large numbers into scientific notation. We'll use the number 459,223. Place a decimal point so that there is only one number to its left (that number cannot be zero). In our example, we would put the decimal point after the 4. This is the coefficient.

4.59223

Count the number of places to the right of the decimal point. In our number there are 5 places after the decimal point. This determines the base. In this case it is 10^5.

4.59223 X 10^5

Wasn't it easier to just write the number 459,223? Yes, but 459,223 isn't really a very big number. What if we wanted to write the number 4,592,230,000,000,000,000. That's 4.59223 quintillion or 4,592230 X 10^18. Unless we are using a computer to do our computations, people usually round off numbers. Which would make 459,223 equal 460,000. In scientific notation, that's 4.6 X 10^5. Our quintillion example would be 4.6 X 10^18. You can always use the names for big numbers, but keep straight the difference between trestrigintillion and trecentillion might not be as easy as the difference between a billion and a trillion.

Did you know that some scientists estimate the number of atoms in the universe is 10^80. Did you know there are 31 million seconds in a year. It would take 31,688 years for a clock to tick off 1 trillion seconds. A googol is 10^100 and a googolplex is 10^googol. Our chart of big numbers gives the names of some big numbers. Visit About Big Numbers to learn interesting facts associated with 31 big numbers. It takes some big numbers to compute the number of atoms in the earth or the weight of the sun in pounds. Visit the quattuorvigintillion page(10^75) to learn how to build a model of the universe using the distance between the earth and sun as the standard for the scale of the model.