Purchase Solution

Combinations-Number of choices

Not what you're looking for?

Ask Custom Question

1. Joey is having a party. He has 10 friends, but his mom told him he could only invite 6 of them. How many choices are there if
a. there are no restrictions
b. there are 2 brothers who will only attend if they can attend together
c. there are 2 girls who each will not attend if the other one does

Attachments
Purchase this Solution

Solution Summary

The expert calculates the number of choices.

Solution Preview

a) there are no restrictions
Total no friends= 10
If there are no restrictions then the no of choices = no of ways of choosing 6 out of 10 =
10 C 6 = (10 x 9 x 8 x 7 x 6 x 5 ) / ( 1 x 2 x 3 x 4 x 5 x 6 ) = 210

Answer : 210

b ) there are 2 brothers who will only attend if they can attend together

There are 2 cases here:

Case 1 ) Both brothers attend
In this case there are 4 more friends to ...

Purchase this Solution


Free BrainMass Quizzes
Geometry - Real Life Application Problems

Understanding of how geometry applies to in real-world contexts

Graphs and Functions

This quiz helps you easily identify a function and test your understanding of ranges, domains , function inverses and transformations.

Probability Quiz

Some questions on probability

Exponential Expressions

In this quiz, you will have a chance to practice basic terminology of exponential expressions and how to evaluate them.

Multiplying Complex Numbers

This is a short quiz to check your understanding of multiplication of complex numbers in rectangular form.