S1 and S2 DOUBTS HERE!!!!

[khi2ruh]

hey im stuck!!

n09 Q5 (a) (i) (ii) and b (ii)

[Saladin]

hey im stuck!!

n09 Q5 (a) (i) (ii) and b (ii)

Sorry m8, I do Edexcel.

[Sweet_03]

Hello , can someone plz help

June2005
Q7 (d)

P( sci | RH ) = P(sci 'n' RH) / P(RH) = (24÷110)/ (110÷148)
thats wat i did , but obviously its wrong
how do you find P(sci 'n' RH)

[Saladin]

Hello , can someone plz help

June2005
Q7 (d)

P( sci | RH ) = P(sci 'n' RH) / P(RH) = (24÷110)/ (110÷148)
thats wat i did , but obviously its wrong
how do you find P(sci 'n' RH)

On it now, will be finished soon iA.

[Saladin]

Hello , can someone plz help

June2005
Q7 (d)

P( sci | RH ) = P(sci 'n' RH) / P(RH) = (24÷110)/ (110÷148)
thats wat i did , but obviously its wrong
how do you find P(sci 'n' RH)

This is how you do it.

(c)You have to find the number of people that are right handed.



So, there are a total of right handers, and a total of students.

So,

(d) This is basically asking, out of 110 right handers, what is the probability that it will be a science student?

So, the number of science students that are right handed, are

Now,

[Sweet_03]

Oh! i was trying to use the formula
okay now it makes sense =')
thank you

[Saladin]

Oh! i was trying to use the formula
okay now it makes sense =')
thank you

Sometimes, you need to understand the whole concept, and understand the feel of the question before attempting it.

[immortal]

Sometimes, you need to understand the whole concept, and understand the feel of the question before attempting it.

this also saves a lot of time..

[Saladin]

this also saves a lot of time..

Just doin ma job. 

[Summer :]]

Find
E( x^2 + 4X - 3)
E(x) = 2.6
and the answer = 15.6
how did they get it ??

[astarmathsandphysics]

Find
E( x^2 + 4X - 3)
E(x) = 2.6
and the answer = 15.6
how did they get it ??
You must know the variance to answer this question. What is it?

[coatseville]

I have two questions...
From the January 2009 paper
question 3e) could you please explain fully how to do this..
and for 2b) why must we use the addition rule? When we didnt in 2a)
Thankyou SO much

[Summer :]]

Find
E( x^2 + 4X - 3)
E(x) = 2.6
and the answer = 15.6
how did they get it ??
You must know the variance to answer this question. What is it?

Var 1.44

[astarmathsandphysics]

Find
E( x^2 + 4X - 3)
E(x) = 2.6
and the answer = 15.6
how did they get it ??
You must know the variance to answer this question. What is it?

Var 1.44
V(X0=E(X^2)-(E(X))^2
1.44=E(X^2)-2.6^2
E(X^2)=1.44+6.76=8.18
E( x^2 + 4X - 3)=E(X^2)-4E(X)-3=8.18-4*2.6-3=8.18-1.4=-5.22

[Blizz_rb93]

June 2001
Question 1 a)
they said to find the mean and the standard deviation for the data given
in the markscheme they gave something different to what i solved
the mean i knew how to do but the standard deviation was the weird part

My solution : Standard Deviation = Square root of [(sum of x^2 divided by n)-(mean)^2]
my answer gives me Math Error

and in the markscheme the answer comes out 4 :/
plz someone help asap
thank you