# AL Maths Venn Diagram Stats Question

https://www.quora.com/profile/Bravewarrior/p-159986922
Here is the question with its solution. I am stuck on part a. When filling out the venn diagram, I got to 0.1 and 0.3, but do not understand how to get to 0.2 and 0.4. Would really appreciate some help!
Original post by pigeonwarrior
https://www.quora.com/profile/Bravewarrior/p-159986922
Here is the question with its solution. I am stuck on part a. When filling out the venn diagram, I got to 0.1 and 0.3, but do not understand how to get to 0.2 and 0.4. Would really appreciate some help!

Bit of a fiddly one, but you have 3 regions to calculate and you know 3 things
P(M), P(E) and the sum of probabilities is 1. Using those you should be able to get the three unknown regions 0, 0.2, 0.4.
Original post by mqb2766
Bit of a fiddly one, but you have 3 regions to calculate and you know 3 things
P(M), P(E) and the sum of probabilities is 1. Using those you should be able to get the three unknown regions 0, 0.2, 0.4.

I am still a bit stuck 😥.
Original post by pigeonwarrior
I am still a bit stuck 😥.

Give the 3 unknown regions letters and write down the 3 simultaneous equations. Upload what youve tried if youre still stuck
(edited 2 months ago)
Original post by mqb2766
Give the 3 unknown regions letters and write down the 3 simultaneous equations. Upload what youve tried if youre still stuck
Quora - A place to share knowledge and better understand the world
This is where I got to, really which is not far at all 😭
I then tried to come up with equations but kept on getting two unknowns which wasn't helpful.
Original post by pigeonwarrior
Quora - A place to share knowledge and better understand the world
This is where I got to, really which is not far at all 😭
I then tried to come up with equations but kept on getting two unknowns which wasn't helpful.

As its members of a book reading club who read either ... the probability of someone lying outside the three rings is 0. So you have 3 equations in 3 variables x,y,z and while it should be fairly straightforward to solve for them, its worth writing the equations out clearly so you dont miss the sum to 1, for instance.
Original post by mqb2766
As its members of a book reading club who read either ... the probability of someone lying outside the three rings is 0. So you have 3 equations in 3 variables x,y,z and while it should be fairly straightforward to solve for them, its worth writing the equations out clearly so you dont miss the sum to 1, for instance.

I have finally finally gotten it... thank you so much! 😀