AP Precalculus
AP Precalc Unit 2A (2.1–2.6): Exam Mock FRQ
Shared by ashtont · Nov 2, 2026 · 0 plays
3 AP-style multi-part FRQs for the Unit 2A AP Readiness test (2.1–2.6): a followers model with residuals and unit change, an algae two-point model with average rate of change, and sequences plus end behavior. Rubric and sample answer for every part.
11 questions across 3 sections. Write your answer, then check it against the rubric and score yourself.
Sample questions
Open an item to see its answer.
(a) Using two points from the table, write two equations that can be used to find a and b for a model of the form P(m) = a·bᵐ. Then find a and b.
Sample answer: Using (0, 12) and (1, 18): 12 = a·b⁰ gives a = 12. 18 = 12·b gives b = 1.5. So P(m) = 12(1.5)ᵐ. (Any two points work: 40.5/18 = b², so b = 1.5.)
(b) Use your model to predict the number of followers after 7 months.
Sample answer: P(7) = 12(1.5)⁷ = 12 × 17.0859 ≈ 205.03 thousand, so about 205,031 followers.
(c) The actual number of followers after 7 months was 198,000. Find the residual and state whether the model overestimates or underestimates.
Sample answer: Residual = actual − predicted = 198 − 205.03 = −7.03 thousand. Negative, so the model overestimates.
(d) Find an equivalent expression for P where the input y is measured in YEARS.
Sample answer: There are 12 months in a year, so m = 12y. P = 12(1.5)^(12y) = 12(1.5¹²)^y ≈ 12(129.746)^y.
(a) Use the given data to write two equations that can be used to find the values of a and b.
Sample answer: A(0) = 3.2 gives 3.2 = a·b⁰. A(10) = 21.5 gives 21.5 = a·b¹⁰.