Find the probability area bound by 93% or 0.93.
0.5 lies to the left of the mean value.
0.93−0.5=0.43 lies to the right of mean.
Find the corresponding z value for 0.43.
It is 1.48.
Use this value to determine the required x value.
You have to use the formula -
z=x−μσ
Solve it for x
x=z⋅σ+μ
Where;
x=?
z=1.48
σ=0.62
μ=98.20
Now put these values in the formula;
x=(1.48⋅0.62)+98.20=0.9176+98.20=99.1176 = 99.12
Temperature that separates top 7% from the bottom 93% is 99.12.
