Venn diagrams

Watch this thread
Moonlight352
Badges: 11
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 4 weeks ago
#1
How is P(AUB) = P (A) + p(B) - p(AnB).

I dont get why because the minus p(AnB) means ur taking away the intersection part?
0
reply
Skiwi
Badges: 13
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report 4 weeks ago
#2
(Original post by Moonlight352)
How is P(AUB) = P (A) + p(B) - p(AnB).

I dont get why because the minus p(AnB) means ur taking away the intersection part?
P(A U B) is the entire inside of the venn diagram. If you add P(A) and the P(B) then you are essentially adding the intersection part twice as P(A) and P(B) both contain the intersection bit. To make up for this you can take away one lot of the intersection P(AnB) to get what P(A U B) is.
3
reply
Moonlight352
Badges: 11
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report Thread starter 4 weeks ago
#3
(Original post by Skiwi)
P(A U B) is the entire inside of the venn diagram. If you add P(A) and the P(B) then you are essentially adding the intersection part twice as P(A) and P(B) both contain the intersection bit. To make up for this you can take away one lot of the intersection P(AnB) to get what P(A U B) is.
Thank you!!!
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Were exams easier or harder than you expected?

Easier (21)
26.58%
As I expected (24)
30.38%
Harder (29)
36.71%
Something else (tell us in the thread) (5)
6.33%

Watched Threads

View All