quiz questions :( (1 Viewer)

[HSC :(]

hey i was jus goin through the quiz questions and im totally thrown off cos these questions r NOTHING like the questions we went through in the workshops... theyre like a million times harder...

can anyone plzzzzz help me with the first question at least plzzzzzzzzz

1. Given S Xi = 20, S Yi = 22, S Xi Yi = 3, S Xi2 =t 75, S Yi2 = 50, n = 15
Evaluate:
(a) S (3 + Yi) + S (5Xi)2
(b) S (5Xi + 4Yi)2



thanx a bunchhhhhhhhhh

 

[Halo]

a) = n*3 + SYi + 25*SXi2 = 45 + 22 + 1875 = 1942

b) = 25*SXi2 + 40*SXi*Yi + 16*SYi2 = 75 + 120 + 800 = 995

 

[elizabethy]

i think the ques were simple...not dat hard!! i got them easily......n i enjoy ecmt.....nething that involves maths .....im obsessed with it !!!

 

[Left-ism]

Originally posted by elizabethy
i think the ques were simple...not dat hard!! i got them easily......n i enjoy ecmt.....nething that involves maths .....im obsessed with it !!!

youre a loser

 

[perfectionist]

Originally posted by Left-ism
youre a loser

hahahaahah!!

:rofl:

 

[elizabethy]

:uhhuh: atleast im better than many others !!

 

[clever angel]

you r the best...arent u!!

 

[xiao1985]

youre a loser

loser or not loser, i find maths interesting ~~~ and i am more or less obessed with it too...
i i don't see why enjoying and getting good marks in maths makes u a loser =p
if that's true, what does it make u if you are gettin crab marks???

 

[elizabethy]

WELL SAID...xiao!!!