AP® Precalculus: Arithmetic & Geometric Sequences — Drill 1

About This Drill

AP® Precalculus: Arithmetic & Geometric Sequences — Drill 1 is a Math practice drill covering arithmetic-geometric-sequences. It contains 5 original questions created by Brian Stewart, a Barron's test prep author with over 20 years of tutoring experience.

Practice arithmetic and geometric sequences for the AP® Precalculus exam with these five questions. Topics include identifying sequence type from tables, writing explicit and recursive formulas, finding missing terms using the geometric mean, and connecting geometric sequences to exponential models.

Questions in This Drill

1. The table below shows selected terms of a sequence.
   
   

   n	a(n)
   1	5
   2	20
   3	80
   4	320

   
   Which of the following best describes this sequence?
2. An arithmetic sequence has first term a(1) = 7 and common difference d = −3. Which of the following gives the explicit formula for the nth term?
3. A colony of bacteria is growing geometrically. On day 4, the population is 4,000. On day 8, the population is 49,000. Assuming the population forms a geometric sequence, what is the population on day 6?
4. A geometric sequence has first term a(1) = 12 and common ratio r = \(\frac{1}{3}\). Which of the following exponential functions matches the sequence values for integer inputs n?
5. A sequence is defined recursively by a(1) = 2 and a(n) = 3 · a(n − 1) for n ≥ 2. Which of the following statements about this sequence is correct?