Unit Review: Arithmetic & geometric sequences

S.1Write arithmetic (with d), geometric (with r), or neither.

1. 1
   $3,12,48,192,\dots$
2. 2
   $3,6,12,24,\dots$
3. 3
   $13,14,16,19,\dots$
4. 4
   $2,-6,18,-54,\dots$

S.2Find each term, or write a rule for the nth term.

1. 5
   The 18th term: $12,13,14,\dots$
2. 6
   The 31st term: $0,3,6,\dots$
3. 7
   The 11th term: $16,14,12,\dots$
4. 8
   The 33rd term: $15,7,-1,\dots$

S.3Answer each question.

1. 9
   A colony starts with $10$ bacteria and doubles every hour. How many bacteria are there after $8$ hours?
2. 10
   A colony starts with $5$ bacteria and doubles every hour. How many bacteria are there after $7$ hours?
3. 11
   A colony starts with $25$ bacteria and doubles every hour. How many bacteria are there after $4$ hours?
4. 12
   A ball is dropped from $192$ inches. Each bounce reaches half the height of the one before. How high does it go on bounce $3$?

S.1Arithmetic or Geometric?

1. 1geometric, $r=4$
2. 2geometric, $r=2$
3. 3neither
4. 4geometric, $r=-3$

S.2Terms & Rules of Sequences

1. 5$29$
2. 6$90$
3. 7$-4$
4. 8$-241$

S.3Sequence Word Problems

1. 9$2,560$ bacteria
2. 10$640$ bacteria
3. 11$400$ bacteria
4. 12$24$ inches