Question

Help with probability

Answer 1

sum of all probabilities must equal 1.
so, add them and equate it to 1
but there are 2 values unknown.,.....

Answer 2

The sum of all probabilities must be __

Answer 3

with only one equation

Answer 4

yeah, that's why I get confused

Answer 5

if any one of the ??? was given, then you could have found out other ???

Answer 6

answer is b , but i dont know why?

Answer 7

:O

Answer 8

Impossibru!

Answer 9

i would have gone with D

Answer 10

but actually answer is B

Answer 11

The answer would be B if and only if the probability of getting A+, A, B+ and B is equal to the probability of getting C+, C, D, F.

But that is not given in the question, so I'd go with Hartnn.

Answer 12

That is, 0.5

Answer 13

oh wait its possible :P

Answer 14

C+ or better = 1- (C or D or E)

Answer 15

P (C+ or better) = 1-P (C or D or E))
=1- (0.22+0.09+0.07)

Answer 16

why we choose c ,d, e ?

Answer 17

sorry, C,D,F

Answer 18

yeahh, but why?

Answer 19

C+ or better means A+ to C+
if we add all probabilities, we get =1
so, A+ to F = 1
(A+ to C+) + (C,D,F) =1
so, (A+to C+) = 1- (C,D,F)

Answer 20

oh, I got it , thank you very much

Answer 21

welcome ^_^

Answer 22

^ that.is.incorrect.

Answer 23

because you don't want 5 out of 8,
you need probabilities of C+ or better, which needs individual probabilities.
you haven't used any of the probabilities given.
also, 0.62 is different from 0.625