Conditional Probability 1 • Sets and Venn Diagrams • Stats2 Ex2A • 🎲

Рет қаралды 32,510

Күн бұрын

Пікірлер: 37

@jiayanfan1651 4 ай бұрын

20:33 I'm just wondering which areas would be shaded if it were A U (B n C)'? Because I usually assume it's union as we are including all of A, but I'm wrong.

@BicenMaths 4 ай бұрын

Yes, that's right! For U we always shade all of both the things we are looking at. U is so much easier than n!

@temi8261 Жыл бұрын

is (CuD)' the same thing as C'uD' ? same with (CnD)' and C'nD' (u and n is meant to say intersection and union)

@BicenMaths Жыл бұрын

No, this is not true. (CUD)’ is everything outside both of the sets (the opposite of (CUD). C’UD’ is shading everything not in C and everything not in D, in other words, everything but the small overlap. Unfortunately the ‘ notation can’t be applied to each part separately if it’s around the whole bracket - they mean different things.

@alexmatcham5682 11 күн бұрын

For 21:00 you said A n B’ n C’ excluded everything outside B and C but I don’t understand this because at the beginning (A n B)’ is not in A and B, so the middle part of the venn diagram is not included. (A n B)’ is A’ n B’ yet the B’ n C’ doesn’t exclude the middle part of the diagram?

@BicenMaths 8 күн бұрын

(A n B)' is not the same as A' n B', which I think has confused you here - it's so hard to communicate the areas in comment though :( :( :(

@borsalinokizaru731 Жыл бұрын

At 20:00, doesn't the complement of (BUC)' also mean the part outside the 3 circles is shaded?

@BicenMaths Жыл бұрын

Yes, but as it is A AND (BUC)', it must also be inside A for it to be shaded, because of the AND (the arch shape)

@alexmatcham5682 11 күн бұрын

At 16:23 what would be the difference between A’ U B’ U C’ and A’ n B’ n C’

@BicenMaths 8 күн бұрын

U means that all of A', B' and C' get shaded - so everything apart from the tiny bit they overlap. But the n means that it has to be outside all three of them, so it the very outside area, not inside any of the loops at all!

@enourmoussultan2783 3 жыл бұрын

Hello, at 19.32, the middle question on that page, is it okay to write it out as AnB'nC'?

@BicenMaths 3 жыл бұрын

Actually no, you can’t write it in that way, as part of the yellow shading is inside B and C, whereas your definition says that it is not in B and not in C!

@enourmoussultan2783 3 жыл бұрын

@@BicenMaths Oh, ok thank you very much

@rev0cs 8 ай бұрын

so sir if two events are not independent, that doesn't mean they are mutually exclusive?

@BicenMaths 8 ай бұрын

No, definitely not!

@rev0cs 8 ай бұрын

@@BicenMaths ok thanks

@studywithyan697 Жыл бұрын

23:00 I have never played with cards and don't know how many ace and diamonds there is, what other general knowledge do we need to know?

@BicenMaths Жыл бұрын

I don't expect there to be something like cards because of this reason - they would always explain the details of a game to make sure it was an even playing field.

@malanhemal6574 2 жыл бұрын

Hi Sir, at 20.02 the second question I wrote, A intersection (A intersection B intersection C) dash. I think it's right

@BicenMaths 2 жыл бұрын

Yep that is also a correct form!

@malanhemal6574 2 жыл бұрын

@@BicenMaths Thank you Sir

@jammydodger1277 4 ай бұрын

hey sir for the middle example at 16:23, is it valid to say (AnB)nC' ?

@jammydodger1277 4 ай бұрын

also what is the formula for P(AuB) when two events are independent please? I have tried googling but keep getting different answers. Is it just the same as the mutually exclusive formula that P(AuB) = P(A) + P(B)?

@BicenMaths 4 ай бұрын

Yes to your first comment - but for the second comment, it's best to draw a Venn to help you find AUB. As they're independent, you can multiply A and B to find AnB and go from there!

@jammydodger1277 4 ай бұрын

@@BicenMaths Thanks so much for this response and all your other quick responses to my queries. They are really taking my understanding to the next level!

@BicenMaths 4 ай бұрын

@@jammydodger1277 You're welcome - I try my best to see all the commenters and viewers as my students and treat them as they would be if they were in my classroom!