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Facts and Figures from all over...
The distance across the observable universe is 1 * 10 (23) miles (one with 23 zeros)
Stephen W. Hawking: "Brief History of Time"
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Dealing with large numbers is quite simple. By writing the large number in scientific notation [that is the first part of the number is stated as and integer and a decimal point and then the fraction and the number 10 with an exponent equal to the number of zeros needed to make up the number.
  To multiply two large numbers, simpily multiply the beginning numbers and then add the exponents together. To divide subtract the exponents to arrive at the answer: