Let's see what happens:
103 X 108 = (10 X 10 X 10) X (10 X 10 X 10 X 10 X 10 X 10 X 10 X 10) = 1011
104 X 104 = (10 X 10 X 10 X 10) X (10 X 10 X 10 X 10) = 108
102 X 103 X 105 = (10 X 10) X (10 X 10 X 10) X (10 X 10 X 10 X 10 X 10) = 1010
Do you see the pattern?
One of the most useful properties of exponents is that, if both numbers have the same base, then to multiply them together, all you have to do is add the exponents. Since in scientific notation, the base is always 10, multiplying numbers in scientific notation is not difficult. In fact it is often easier to multiply two numbers in scientific notation than it is to multiply the same numbers in decimal notation! Look at all the zeroes you have to count above!
Practice multiplying these numbers:
105 X 109
107 X 106 X 105
1027 X 1032
102 X 10-3 X 105
Now check your answers.
Questions? Ask the designer, Jim Heath
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