Question

does anyone know how to do these?
1.) 80,81,84, 91, 99, 50, 93, 100-standard deviation
2.) 78, 66, 62,46, 78, 81, 72-median

Answer 1

yes

Answer 2

median is easiest; its the number that is in the middle of the pile.

sort them from high to low (or l;ow to high doesnt matter) and pick the number in the middle of the pack

Answer 3

i did that but the answer was wrong

Answer 4

standard deviation by hand is alot more complicated

Answer 5

what answer did you pick?

Answer 6

46 62 66 72 78 78 81
1 2 3 |4| 5 6 7
^
id pick 72 for the median

Answer 7

i got 72.

Answer 8

it might just be my computer...messing up

Answer 9

yeah, humna error on the programing end happens too.

the median IS 72 regardless

Answer 10

you need the standard deviation by hand or by calculator?

Answer 11

calculator

Answer 12

if i remember the steps by hand

find the mean

subtract mean from data

square results

add up results

divide by either (n-1) for sample, or (n) for population

unsquare it by taking the square root

Answer 13

calculator needs a statistics feature; like my ti83 :)

Answer 14

uhm, okay. i think i get it. thank you!

Answer 15

as long as i entered it into the list right i get:

sample sd (15.98)
population sd (14.95)

since ther eis no indication that this is really a sample, id go with the population sd

Answer 16

thats right!

Answer 17

yay!! that means my $100 calculator for stats class works :)

but then again, you say it says the median aint 72 so i gotta wonder ;)

Answer 18

it was my computer. i put it in again and it worked! thanks a lot! one day ill learn how to do this stuff by myself!

Answer 19

during stats class i was a bit lost since it was alot of memorizing formulas; but i seem to have acquired a simple understanding of it as of late ...