Question 436745
{{{mu = np}}} and {{{sigma = sqrt(npq)}}}

==> np = 12, and 2.683 = {{{sqrt(npq) = sqrt(np(1-p))}}}

==> {{{2.683 = sqrt(12(1-p))}}}
==> 7.198489 = 12(1-p)
==> 0.5999 = 1-p , to 4 decimal places.
==> .4001 = p, or p = 0.4 to the nearest tenth.
==> np = 12 ==> 0.4n = 12 ==> n = 30.