Question

True or False?
Probabilities can be added only when events are independent.

Answer 1

hint:

P(a or b) = P(a) + P(b)

does that help?

Answer 2

that's only true some of the time though

Answer 3

False

Answer 4

So its false?

Answer 5

it's only true if the two events are mutually exclusive

Answer 6

yep

Answer 7

Yeah It's false.

Answer 8

Oh okay thanks!

Answer 9

it's not exclusive to independent events

Answer 10

What about True or False
When tossing 2 coins, P(at least 1 head) = P(not all tails).

Answer 11

List out the sample space

HH
HT
TH
TT

and tell me what you think

Answer 12

hmm

Answer 13

True!

Answer 14

it is true

Answer 15

Thanks!

Answer 16

you'll see that there are 3 out of 4 ways to get at least one head (HH, HT, TH) and there are 3 out of 4 ways to not get all tails (everything but TT)