Around
Around[x,δ] represents an approximate number or quantity with a value around x and an uncertainty δ.
Around[x,{δ-,δ+}] represents a number or quantity with a value around x and asymmetric uncertainties δ-, δ+.
Around[dist] gives an approximate number or quantity around the mean of the distribution dist, with an uncertainty corresponding to the standard deviation of the distribution.
Around[list] gives an approximate object around the mean of the elements of list and with an uncertainty corresponding to their standard deviation.
Around[s] gives an approximate object derived from the number, interval or string specification s.
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