Step-by-step explanation:
there must be some typos here. but I try to address the right issues.
there is nothing under (a). so, really nothing to answer.
(b)
there are 20 sweets in her bag. 9 if the 20 are yellow.
so, the probability is the ratio of desired possibilities vs. total possibilities.
that is, tada! 9/20
that is the probabilty for Samira to pick a yellow sweet.
[1] (i)
again, 20 sweets to start with.
6 are green.
when she picks the first one, her probability to pick a green one is 6/20 = 3/10 = 0.3
and now, under the assumption that this came true, she picks another sweet.
this time she had only 19 left, and 5 of them are green.
so, this probabilty is 5/19
now both events need to happen for the case we are discussing. there is no overlapping, no ors, ifs and buts. it is just the product of both probabilities.
3/10 × 5/19 = 15/190 = 3/38
I think that is what the description asks for.
(ii)
that probability is
first selection is red and second is not red +
first selection is green and second is not green +
first selection is yellow and second is not yellow
so,
red and not red
5/20 = 1/4 red
15/19 not red (there are still 15 sweets of other colors in the bag, but again now only 19 total).
red and not red = 1/4 × 15/19 = 15/76 = 0.1974
green and not green
6/20 = 3/10 = green
14/19 = not green
green and not green = 3/10 × 14/19 = 52/190 = 26/95 =
= 0.2737
yellow and not yellow
9/20 = yellow
11/19 = not yellow
yellow and not yellow = 9/20 × 11/19 = 99/380 = 0.2606
so, now assuming up all 3 possibilities ("or" = sum) gives us the general possibility of selecting two different colors
= 0.7316
