Math Problem

[Kirbs17]

I know its nerdy, but whatever. My prof. hands out math problems as brain teasers in stats, thought Id share one or two of em for you guys:

An Institution awards scholarships to the top 2% of its students. If yearly Grade Point Average at the instituion are normally distributed with a mean of 4.5 and a standard deviation of 2, what G.P.A must a student get in order to win a scholarship?

took me quite a while to get it.

[lastprodigy]

6.9

[Kirbs17]

close, real damn close

[lastprodigy]

serious ? :confused:

[Pihsiak]

Better than what I came up with....


Z = (Y-U)/O
U = 4.5
O = 2
.02 in Zcal format is +2.054

2.054 = (Y-4.5)/2
2x2.054 = Y -4.5
4.108 = Y - 4.5
4.108+4.5 = Y

Y = 8.608

[Kirbs17]

Our prof, ta and grad student all came up with 6.45 as a minimun G.P.A that one has to have to achieve a scholarship.

lol i'll try to write the formula:

Z=(X-Mean)/Standard deviation (this works because it is a normally distributed problem)

Z=.02 which equals .9798 (Cumulative probabilites for the standard normal distribution)

.9798=(X-4.5)/2

times by 2, add the 4.5 = 6.45

[Pihsiak]

So i was on the right track except i got the wrong Z value


I guess i should have used the normal dist table instead of some online generator...

[Kirbs17]

Originally posted by Pihsiak
So i was on the right track except i got the wrong Z value


I guess i should have used the normal dist table instead of some online generator...

yea, no worries, i didnt expect anyone would actually nerd it up with me, but thats awesome. lemme know if you want me to post some different one?

[Pihsiak]

What are you in?

I'm in the 400 lvl stat courses... was just too lazy to dig up my tables, just googled normal dist generator.

[Kirbs17]

Introduction to business statistics, at Red Deer College