1. ## Homework Help Please :D

Sita puts 5 balls in Box A and 4 Balls in Box B.
The balls are numbered.

Box A-balls numbered 1-5
Box B-balls numbered 1-4

What is the probability that both balls have odd numbers?

I have done some working out and i think the answer may be 3/10
Can anyone please confirm this for me and tell me how they got to that answer.

Thankyou.

2. Originally Posted by solid icy
Sita puts 5 balls in Box A and 4 Balls in Box B.
The balls are numbered.
Box A-balls numbered 1-5
Box B-balls numbered 1-4

What is the probability that both balls have odd numbers
I have done some working out and i think the answer may be 3/10
Can anyone please confirm this for me and tell me how they got to that answer.

Thankyou.
$\frac{\binom{3}{1} \binom{2}{0}}{\binom{5}{1}} \cdot \frac{\binom{2}{1} \binom{2}{0}}{\binom{4}{1}}= \frac{3}{5} \cdot \frac{2}{4}= \frac{3}{10}$

3. Hello, solid icy!

You are correct!

Sita puts 5 balls in Box A and 4 balls in Box B.
. . Box A: balls are numbered 1 - 5
. . Box B: balls are numbered 1 - 4
A ball is drawn at random from each box.
What is the probability that both balls have odd numbers?
This problem is small enough to make a complete list.

Here are the outcomes:

. . $\begin{array}{cccc}{\color{red}(1,1)} & (1,2) & {\color{red}(1,3)} & (1,4) \\ (2,1) & (2,2) & (2,3) & (2,4) \\ {\color{red}(3,1)} & (3,2) & {\color{red}(3,3)} & (3,4) \\ (4,1) & (4,2) & (4,3) & (4,4) \\ {\color{red}(5,1)} & (5,2) & {\color{red}(5,3)} & (5,4) \end{array}$

Of the twenty outcomes, six have two odd numbers.

Therefore: . $P(\text{both odd}) \;=\;\frac{6}{20} \;=\;\boxed{\frac{3}{10}}$