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decimal place





The number of places to the right of a decimal point required to specify a real number to a certain accuracy. For example, the number 4.893302 to three decimal places is written 4.893 (3 d.p.). To five decimal places the same number is 4.89330 (5 d.p.). The convention is to round up the last decimal place if the digit after that place is five or greater, and to round down if it is four or less. Thus the numbers 239.705 and 239.706 are both 239.71 (2 d.p.) to two decimal places, whereas the number 239.704 to two decimal places is 239.70 (2 d.p.). See also significant digits.


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   • APPROXIMATIONS AND AVERAGES