Sequence and series-Write the first four terms of the following sequence whose general term is given.

Question 1 Write the first four terms of the following sequence whose general term is given.
an = 3n
A. 3, 9, 27, 81 
B. 4, 10, 23, 91 
C. 5, 9, 17, 31 
D. 4, 10, 22, 41
Question 2 The following are defined using recursion formulas. Write the first four terms of each sequence.
a1 = 3 and an = 4an-1 for n ≥ 2
A. 3, 12, 48, 192 
B. 4, 11, 58, 92 
C. 3, 14, 79, 123 
D. 5, 14, 47, 177
Question 3 If three people are selected at random, find the probability that they all have different birthdays.
A. 365/365 * 365/364 * 363/365 ≈ 0.98 
B. 365/364 * 364/365 * 363/364 ≈ 0.99 
C. 365/365 * 365/363 * 363/365 ≈ 0.99 
D. 365/365 * 364/365 * 363/365 ≈ 0.99
Question 5 Write a formula for the general term (the nth term) of each arithmetic sequence. Do not use a recursion formula. Then use the formula for an to find a20, the 20th term of the sequence. 
an = an-1 - 10, a1 = 30
A. an = 60 - 10n; a = -260 
B. an = 70 - 10n; a = -50 
C. an = 40 - 10n; a = -160 
D. an = 10 - 10n; a = -70
Question 6 Use the formula for the sum of the first n terms of a geometric sequence to solve the following.
Find the sum of the first 12 terms of the geometric sequence: 2, 6, 18, 54 . . .
A. 531,440 
B. 535,450 
C. 535,445 
D. 431,440
Question 7 The following are defined using recursion formulas. Write the first four terms of each sequence.
a1 = 4 and an = 2an-1 + 3 for n ≥ 2
A. 4, 15, 35, 453 
B. 4, 11, 15, 13 
C. 4, 11, 25, 53 
D. 3, 19, 22, 53
Question 8 If 20 people are selected at random, find the probability that at least 2 of them have the same birthday.
A. ≈ 0.31 
B. ≈ 0.42 
C. ≈ 0.45 
D. ≈ 0.41
Question 10 Write the first six terms of the following arithmetic sequence. 
an = an-1 + 6, a1 = -9
A. -9, -3, 3, 9, 15, 21 
B. -11, -4, 3, 9, 17, 21 
C. -8, -3, 3, 9, 16, 22 
D. -9, -5, 3, 11, 15, 27
Question 12 
Write the first six terms of the following arithmetic sequence.
an = an-1 - 10, a1 = 30
A. 40, 30, 20, 0, -20, -10 
B. 60, 40, 30, 0, -15, -10 
C. 20, 10, 0, 0, -15, -20 
D. 30, 20, 10, 0, -10, -20 
Question 14 How large a group is needed to give a 0.5 chance of at least two people having the same birthday?
A. 13 people 
B. 23 people 
C. 47 people 
D. 28 people
Question 15 You volunteer to help drive children at a charity event to the zoo, but you can fit only 8 of the 17 children present in your van. How many different groups of 8 children can you drive?
A. 32,317 groups 
B. 23,330 groups 
C. 24,310 groups 
D. 25,410 groups
Question 16 Find the indicated term of the arithmetic sequence with first term, a1, and common difference, d. 
Find a200 when a1 = -40, d = 5
A. 865 
B. 955 
C. 678 
D. 895
Question 17 An election ballot asks voters to select three city commissioners from a group of six candidates. In how many ways can this be done?
A. 20 ways 
B. 30 ways 
C. 10 ways 
D. 15 ways 
Question 18 Write the first six terms of the following arithmetic sequence.
a1 = 5/2, d = - ½
A. 3/2, 2, 1/2, 1, 1/4, 0 
B. 7/2, 2, 5/2, 1 ,3/2, 0 
C. 5/2, 2, 3/2, 1, 1/2, 0 
D. 9/2, 2, 5/2, 1, 1/2, 0
Question 19 Write the first six terms of the following arithmetic sequence.
an = an-1 - 0.4, a1 = 1.6
A. 1.6, 1.2, 0.8, 0.4, 0, -0.4 
B. 1.6, 1.4, 0.9, 0.3, 0, -0.3 
C. 1.6, 2.2, 1.8, 1.4, 0, -1.4 
D. 1.3, 1.5, 0.8, 0.6, 0, -0.6
Question 20 Use the formula for the sum of the first n terms of a geometric sequence to solve the following.
Find the sum of the first 11 terms of the geometric sequence: 3, -6, 12, -24 . . .
A. 1045 
B. 2108 
C. 10478 
D. 2049