# A few basic probability problems

• May 19th 2013, 08:41 PM
jrbraves26
A few basic probability problems
1. 20 people go to a movie theater, and have a chance to win a \$100 gift card, \$50 gift card, 2 tickets, or a free popcorn. How many ways can the prizes be awarded?

2. Five couples go to the baseball game. How can the seats be arranged if each couple wants to sit together and the order within each couple does not matter?

3. A man's wallet contains 4 twenties, 3 fifties, and 3 tens. What is the probability that his son will randomly take out a twenty, given that he already took out a ten?

4. Pizza Hut has 10 toppings for pizza. How many ways can someone chose 3 toppings for one pizza?
• May 19th 2013, 11:48 PM
chiro
Re: A few basic probability problems
Hey jrbraves26.

Can you show us your attempts please? Even if its a partial one, it's better than nothing.
• May 20th 2013, 06:14 PM
jrbraves26
Re: A few basic probability problems
Chiro,

Thank you for the prompt reply. The reason I am asking these problems here is because I do not have an idea of where/how to start. I believe that these are permutations/combinations, if that helps.

1. 80 ways? 8 * 4 = 80, I feel like this is wrong.

2.

3.

4. 10 *9 *8 maybe?
• May 21st 2013, 04:24 AM
chiro
Re: A few basic probability problems
Hint: How many ways can the first prize awarded? (You have 20 people and 4 prizes so you have (Person1,Prize1) (Person2,Prize1) ... (Last Person,Last Prize)).

Use that hint and apply it to the next way to get the next prize until you are finished with awarding prizes.