Question 903026
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Hi,
TI syntax is normalcdf(smaller, larger, µ, &#963;).
Note: The -100 is used as the smaller value to be at least 5 standard deviations from the mean.
a. P(x < 3) = normalcdf(-100, 3, 7.2, 2.3)
0r P(z < -1.8261)
b. z = invNorm(.98)=( X-7.2)/2.3
2.3invNorm(.98) + 7.2 = X, number of years needed for the guarantee
c. P(x < 8) = P(z < .8/(2.3/sqrt(20)) )