Question 456937
{{{0.75 - 1.96*sqrt((0.75*0.25)/400) <= p <= 0.75 + 1.96*sqrt((0.75*0.25)/400)}}}
<==> {{{0.75 - 0.0424 <= p <= 0.75 + 0.0424}}}

<==> {{{0.7076 <= p <= 0.7924}}}