HP -225 Owner's Manual page 75

Part 2: Calculate the mean of the four exam grades.
{=~} {¥} ¥=81.5000 Calculates the mean.
Part 3: Estimate the number of hours of tutoring necessary to achieve
a grade of 80.
80 {LR. } {&#} =x=3.2532 Calculates estimate of
x for y = 80.
Part 4: Estimate the grade after 5 hours of tutoring.
5 {LR.} {5} $=90.6154 Calculates estimate of
y for x = 5.
100 + 0)
50 +
4
6
5: Statistical Calculations 67