Mathematics: Post your doubts here!

[reina81]

Well, this was how I'd solved it before:

Simply 'choose' 2 Gs out of 3, and the remaining 7 letters can be completely random!

G G _ _ _ _ _ _ _...............[consider GG to be 'attached' together so that it can alternate in 2! ways]

n = 2! x 3c2 x 7!.................. [but don't forget that there are 3 recurring Es too!]
..............3!
...= 5040...... Q.E.D


P.S. If you're still uncertain, let me know. I'll work in it one more time.

but then what happens to the other G?

 

[smartangel]

smartangel. Apparently u need a tutor. Too many doubts :O

thats not a very helpful comment a few hours before the paper you know

 

[reina81]

ON 11 P63 Q2, i, I made a correct tree diagram but i keep getting 31/30 as the probability

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w11_ms_63.pdf

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w11_ms_63.pdf

 

[mybch]

Can anyone please explain 4 (iii)
it would be of great help
this is mechanics 2 btw

 

[Khan_971]

thats not a very helpful comment a few hours before the paper you know

Im sorry. Well. good uck. But my, p63 w11 is HARD

 

[smartangel]

Im sorry. Well. good uck. But my, p63 w11 is HARD

good luck to you as well! and thanks a lot for helping me out...

 

[smartangel]

Im not sure. but i think u can take probability at 63 to be 0.75 since it is upper quartile. u do know the mean.
P(63-mean/ S.D) =.75
try

yeah thats how we do it! thanks!

 

[smartangel]

Remember the fi thing i said before, use that formula

P( k-mean/standard devation <Z< 128-mean/s.d) = .7465

yeah i tried that but couldnt get the answer..could you plz do it?

 

[hassam]

Well, this was how I'd solved it before:

Simply 'choose' 2 Gs out of 3, and the remaining 7 letters can be completely random!

G G _ _ _ _ _ _ _...............[consider GG to be 'attached' together so that it can alternate in 2! ways]

n = 2! x 3c2 x 7!.................. [but don't forget that there are 3 recurring Es too!]
..............3!
...= 5040...... Q.E.D


P.S. If you're still uncertain, let me know. I'll work in it one more time.

CNT GET UR WAYYY,,,,,,,,my stratergy was too find two Gs 2gether,,,,,,without emphaisizing exctly 2 meaning i ll have calculated both 2 and 3 and then subtract that from exactly 3....bt dount knw where's the problem

 

[Richmondtan]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s03_qp_6.pdf

and

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s11_qp_63.pdf

in S03 question 7i), the midpoint was found using (0+5)/2 but in S11 q3 iii) the midpoint was found using (0+9)/2

how come?

 

[leadingguy]

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_s10_qp_63.pdf
http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_s10_ms_63.pdf

question 3 part iii how to do?/ m unable to get
plz any one

 

[JulyMei]

help???

thanks in advance

 

[mukki]

View attachment 10603

help me on 4 ii)

E=summation easy calculate E(x) because its the same for both. E(x) = 245 +E(60)=4445
then find E(x-50) = Ex -E50=4445-70*50=945

 

[mukki]

help???

thanks in advance

this question has been solved three to 4 times plz check from pages 170 onwards

 

[Richmondtan]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_63.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_ms_63.pdf

question 3 part iii how to do?/ m unable to get
plz any one

Since probability of going to park is 0.6,hence not going is 0.4. The dog barks when goes to park = 0.6x 0.35 aand not going to park = 0.4x0.75.Sum it up =)

 

[JulyMei]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_63.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_ms_63.pdf

question 3 part iii how to do?/ m unable to get
plz any one

use "npq"

n=30
p=0.6
q=0.4

30 x 0.6 x 0.4 = 7.2

 

[leadingguy]

Since probability of going to park is 0.6,hence not going is 0.4. The dog barks when goes to park = 0.6x 0.35 aand not going to park = 0.4x0.75.Sum it up =)

sorrY bt have askd fr the last part any ways thanx fr ur co-operation i gt ma answer

 

[reina81]

this question has been solved three to 4 times plz check from pages 170 onwards

i know how to solve this i was just wondering when should we use this method and when do we just use the probability they've given?

 

[JulyMei]

i know how to solve this i was just wondering when should we use this method and when do we just use the probability they've given?

the probability given will be still using it.. and when they say "within", we hv to find the lower and upper boundary.

 

[shan5674]

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w10_qp_63.pdf

why is there a x2 in Q7(ii)?