Question 1070681
Using EXCEL's NORMSINV,
{{{z=1.080}}}
.
.
.
Using symmetry,
{{{1-0.83=0.17}}}
Half goes to the right hand side and half goes to the left.
So find z such that {{{z=0.17/2=0.085}}}
Using EXCEL's NORMSINV,
{{{z[1]=-1.3722}}}
Using symmetry,
{{{z[2]=1.3722}}}