• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Mathematics: Post your doubts here!

Messages
81
Reaction score
5
Points
18
need to clear my doubt.. when is the time to use lower/upper boundary in normal distribution?? for instance mean=20 P(x>18)
when to standardize I often see like this Z=(18.5-20)/(standard deviation.. hmmm
 
Messages
44
Reaction score
7
Points
8
need to clear my confusion please....when exaclty we use the continuity correction in S1 problems like for example in nov 06 question 5)ii) the mark scheme used the 10 as it is without cc but in june 2011 63 question 5)iii) the mark scheme used the cc......please can u help me in this??
 
Messages
176
Reaction score
104
Points
53
need to clear my doubt.. when is the time to use lower/upper boundary in normal distribution?? for instance mean=20 P(x>18)
when to standardize I often see like this Z=(18.5-20)/(standard deviation.. hmmm
Usually there's the phrase USE a Suitable approximation :)
 
Messages
176
Reaction score
104
Points
53
help me with this plzzz
See. 2 people getting odd numbers froma total of 10 mugs
1st person is who we'll deal with:
can get 1 ,3 ,5 ,7 ,9
Possibilities: 10C1, 10C3, 10C5, 10C7, 10C9
add them up to get total arrangements.
 
Messages
47
Reaction score
9
Points
18
Does anybody here have a Statistics ebook they would not mind sharing? Please? Please?
 
Messages
176
Reaction score
104
Points
53
need to clear my confusion please....when exaclty we use the continuity correction in S1 problems like for example in nov 06 question 5)ii) the mark scheme used the 10 as it is without cc but in june 2011 63 question 5)iii) the mark scheme used the cc......please can u help me in this??
CC usually kicks in when theres a ≥ or <= of some value. :)when theres 'at least' or 'should not be greater than'
 
Messages
47
Reaction score
6
Points
18
Find the number of different ways in which the 9 letters of the word GREENGAGE can be
arranged if exactly two of the Gs are next to each other.
Now in this question I understand the way to do it but when I was trying to do it in different way, I hit a wall. I know I'm doing something wrong I just can't figure what is it.
This is what I want to do:
Total number of arrangements - number of arrangements where none of the G's are next to each other.
9!/(3!*3!) - (7*6*5*(6!/3!)). THE ANSWER IS NEGATIVE. WHAT AM I DOING WRONG?
 
Messages
21
Reaction score
2
Points
13
i don't understand why sometimes we square or cube our answers? especially in those questions where they asked the probability of something happened for the next three days or next five churches? can someone please explain it for me? thanks
 
Top