Answer:
y = 10
Step-by-step explanation:
Using the sine ratio in the right triangle and the exact value
sin30° =
, then
sin30° =
=
=
( cross- multiply )
2y = 20 ( divide both sides by 2 )
y = 10
The answer relies on whether the balls are different or not.
If they are not, which is almost certainly what is intended.
If they are, the perceptive is a bit different. Your
expression gives the likelihood that a particular set of j balls
goes into the last urn and the other n−j balls into the other urns.
But there are (nj) different possible sets of j balls, and each of
them the same probability of being the last insides of the last urn, so the
total probability of completing up with exactly j balls in the last
urn is if the balls are different.
See attached file for the answer.
9 a
------ = -----
a 5
a^2 = 45
a = 3<span>√5
</span>
4 b
------ = -----
b 5
b^2 = 20
b = 2√5
answer:
a = 3√5
b = 2√5
hope it helps
Its letter A 3/20 i divided it