flappyduck21
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Find p,q,r please
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Eri Brace
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(Original post by flappyduck21)
Find p,q,r please
Where was the last place you saw them
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flappyduck21
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(Original post by flappyduck21)
Find p,q,r please
(Original post by Eri Brace)
Where was the last place you saw them
On the M5 evading a police chase 😐 (picture of q is below 😉)
Last edited by flappyduck21; 1 month ago
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flappyduck21
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(Original post by flappyduck21)
Find p,q,r please
Here is the question
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gyuigygh
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You got p right, it's 0.2 coz A is 0.4 in total.

For q you know P(A or B) is 0.7 so everything in both circles must add to 0.7 and you know the total of circle A is 0.4

So q is 0.7-0.4
q=0.3
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Eri Brace
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P=0.2
q=0.3
r=0.2
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flappyduck21
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(Original post by gyuigygh)
You got p right, it's 0.2 coz A is 0.4 in total.

For q you know P(A or B) is 0.7 so everything in both circles must add to 0.7 and you know the total of circle A is 0.4

So q is 0.7-0.4
q=0.3
Hmm i understand where ur coming from.. But I got 0.3 in my working and then i used that and took it away from the value of p (0.2) and got 0.1 for q...

The reason i took it away was to get the value of q on its own.. Or does q represent the whole circle??
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flappyduck21
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(Original post by Eri Brace)
P=0.2
q=0.3
r=0.2
Does q represent the value of the whole circle
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gyuigygh
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(Original post by flappyduck21)
Does q represent the value of the whole circle
?
No just the blue bitName:  Screenshot_20200806_012939.jpg
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gyuigygh
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(Original post by flappyduck21)
Hmm i understand where ur coming from.. But I got 0.3 in my working and then i used that and took it away from the value of p (0.2) and got 0.1 for q...

The reason i took it away was to get the value of q on its own.. Or does q represent the whole circle??
How did you get 0.3?
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flappyduck21
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(Original post by gyuigygh)
How did you get 0.3?
So P(A or b) = p(a) + p(b)
0.7. = 0.4. + p(b)

Hence 0.7 -0.4 = 0.3 for p(b)
Then i did q = 0.3 -0.2 = 0.1
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gyuigygh
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Name:  Screenshot_20200806_013515.jpg
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Also, this formula(in red) is only for mutually exclusive events (circles that are not touching as mutually exclusive means impossible to happen at same time so no overlap)

A and B are not mutually exclusive to each other as there is overlap.
A and C are mutually exclusive.
B and C are mutually exclusive.

So you cannot use that formula for P(A or B) ,
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flappyduck21
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(Original post by gyuigygh)
Name:  Screenshot_20200806_013515.jpg
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Also, this formula(in red) is only for mutually exclusive events (circles that are not touching as mutually exclusive means impossible to happen at same time so no overlap)

A and B are not mutually exclusive to each other as there is overlap.
A and C are mutually exclusive.
B and C are mutually exclusive.

So you cannot use that formula for P(A or B) ,
Ahh yeh your right! I inferred from what the question said 'the probability of a and b is 0.7' 😅
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gyuigygh
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(Original post by flappyduck21)
So P(A or b) = p(a) + p(b)
0.7. = 0.4. + p(b)

Hence 0.7 -0.4 = 0.3 for p(b)
Then i did q = 0.3 -0.2 = 0.1
That formula is for mutually exclusive events use
P(A or B) =P(A) +P(B) - P(A intersect B)
if you wanna use a formula
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flappyduck21
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(Original post by gyuigygh)
That formula is for mutually exclusive events use
P(A or B) =P(A) +P(B) - P(A intersect B)
if you wanna use a formula
Ahh yeh that looks good makes sense now! Thanks for the help 😊
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gyuigygh
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Np
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flappyduck21
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#17
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Got another

(Original post by gyuigygh)
Np
Got one more question that I need help in.. Mind having a look?
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gyuigygh
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(Original post by flappyduck21)
Got another


Got one more question that I need help in.. Mind having a look?
Go on then, the night is still young
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flappyduck21
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#19
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(Original post by gyuigygh)
Np
Name:  1596674692215190946388.jpg
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(Original post by gyuigygh)
Go on then
Name:  15966747243901318240936.jpg
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gyuigygh
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For a multiply them I think.
For b have a go urself first
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