if p(A)=p(B)=.15, p(C)=.4, and p(D)=2p(E). find the probs of D and E

Question

amistre64 · Answer

are we to assume that they all add up to 1?

anonymous · Answer

yes

amistre64 · Answer

if so, then the ration of D to E is 1 to 2

1 - A - B - C gives us what is left to divvy up

dividing that by 3 allows us to sort it by a ration of 1 to 2.  D=1/3 E = 2/3

does that make sense?

anonymous · Answer

not really

amistre64 · Answer

if they all add to one we have:

A+B+C+D+E = 1

A+B+C+D+2D = 1

A+B+C+3D = 1

3D = 1-A-B-C

D = (1-A-B-C)/3

anonymous · Answer

ok

amistre64 · Answer

D is 1/3 of whats left ..  therefore E is 2/3 of whats left

anonymous · Answer

i just checked the back of the text book and it says D=.20, E=.10

amistre64 · Answer

yes, that would be what we get.  i mighta seen the E,D parts a little backwards tho :)

anonymous · Answer

more explanation pls

amistre64 · Answer

ive really explaned it as much as i can ... i need to know what you are seeing it as.

amistre64 · Answer

all this is is adding parts to equal 1

amistre64 · Answer

they give you the value of most of the parts, and a relationship between the 2 unknowns

anonymous · Answer

tx alot. i,m so grateful