Given:
- 15 identical balloons.
- 6 identical pencils.
- 3 identical erasers.
- 3 children.
Each child must get at least 4 balloons and 1 pencil. First, let's distribute the minimum required balloons and pencils to each child:
For the Balloons:
Each child gets 4 balloons. So, for 3 children: \(3 \times 4 = 12\) balloons are given. We're left with \(15 - 12 = 3\) balloons to be distributed.
Now, let's use the formula for distributing \(n\) identical objects among \(r\) people/groups.
The formula is:\((^{n+r-1}C_{r-1})\)
Where: - \(n\) = number of identical objects - \(r\)= number of groups/people
Here, \(n = 3\) (remaining balloons) and \(r = 3\) (children).
Number of ways to distribute 3 identical balloons among 3 children
= \(^{3+3-1}C_{3-1}\)
\(= \space^{5}C_{2}\)
\(= \frac{5!}{2!3!}\)
\(= 10\)
For the Pencils: Each child gets 1 pencil.
So, for 3 children: \(3 \times 1 = 3\) pencils are given.
We're left with \(6 - 3 = 3\) pencils to be distributed.
Using the formula again, for \(n = 3\) pencils among \(r = 3\) children:
Number of ways to distribute 3 identical pencils among 3 children = \(^{5}C_{2} = 10\)
For the Erasers: There are 3 identical erasers and 3 children.
So, using the formula for \(n = 3\) erasers and \(r = 3\) children:
Number of ways to distribute 3 identical erasers among 3 children = \(^{5}C_{2} = 10\)
Now, the total number of ways is the product of all the individual ways:
\(Total = 10 (for \space balloons) \times 10 (for\space pencils) \times 10 (for \space erasers)\)
\(Total = 1000\)
So, there are 1000 ways to distribute the items among the children satisfying the given conditions.
Based upon the results of regular medical check-ups in a hospital, it was found that out of 1000 people, 700 were very healthy, 200 maintained average health and 100 had a poor health record.
Let \( A_1 \): People with good health,
\( A_2 \): People with average health,
and \( A_3 \): People with poor health.
During a pandemic, the data expressed that the chances of people contracting the disease from category \( A_1, A_2 \) and \( A_3 \) are 25%, 35% and 50%, respectively.
Based upon the above information, answer the following questions:
(i) A person was tested randomly. What is the probability that he/she has contracted the disease?}
(ii) Given that the person has not contracted the disease, what is the probability that the person is from category \( A_2 \)?