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## 'Time to Evolve 2' printed from http://nrich.maths.org/

What are the formulae for the expectation
of a sum and the variance of a sum?

In creating the trial simulation, you could use the spreadsheet
functions

RAND() returns a
$\mbox{U}[0,1]$ random variable.

COUNTIF($A$5:$A$1005,"=96")
counts the number of cells in the range$A$5:$A$1005 which equal the
value 96