Chapter 8:  Sequence, Series and Probability

 

1.      Find the first three terms of the sequence:

a) {1 - 2n}      b) {9}      c) {1 + nn}

 

Arithmetic Sequence of the nth Term

a n = a 1 + (n - 1)d

 

Example:  The first three terms of an arithmetic sequence are 1, 1.5, and 2.     

                 Find the 5th term.

Solution:  The difference is 1.5 - 1.0 = 0.5

                 a 1 = 1, d = 0.5, and n = 5 in a n = a 1 + (n - 1)d is 3.

 

 

2.      Find the 5th and 10th term of arithmetic sequence:

a)     1, 5, 9, 18,...

b)     x - 8, x - 3, x + 2, x + 7,...

c)      -5, -3.5, -2, -0.5,...

 

Geometric Sequence of the nth Term

a n = a 1 r n-1

 

 

3.      Find the 5th and 10th term of geometric sequence:

a)     200, -20, 2, -0.2,...

b)     4, -6, 9, -13.5,...

d)     3, 3x+1, 32x+1, 33x+1,...

 

Definition of the Probability of an Event

Let S be the sample space of an experiment and E an event.  The probability P(E) of E is given by

 

P(E) = n(E)/n(S)

 

4.      A 6-member committee is to be chosen by drawing names of individuals form a hat.  If the hat contains the names of 8 men and 14 women, find the probability that the committee will consist of 3 men and 3 women.

 

5. 

 


                                                    

                                                        

                                                                 

                                                                                         

                                                                          

                                                                          

 

 

      The figure above is a small version of a probability demonstration device.  A  

      small ball is dropped into the top of the maze and tumbles to the bottom.                   

      Each time the ball strikes an obstacle, there is a 50% chance that the ball will   

      move to the left.  Find the probability that the ball ends up in a slot.