25 Challenging SAT Problems

25 Challenging SAT Problems These questions are all variations of the hardest problems from the Fall 2024 and Spring 2025 SATs. The difficulty of these problems is comparable to the difficulty of the final 3 problems on the hardest module 2. This set is also fairly comprehensive, meaning that it covers almost every challenging topic that you can expect to see. If you find these problems too challenging, check out my book, SAT Math from the Ground Up at learnsatmath.com. It will teach you... you’ll never guess this one... the SAT math from the ground up. Rather than focusing on how to solve problems, it’ll teach you why the math really works, which is essential to tackle problems of this difficulty. These 25 problems follow the book’s ordering: • Chapter 1: Algebra & Functions - Q1-5 • Chapter 2: Exponentials - Q6-8 • Chapter 3: Quadratics - Q9-14 • Word Problems (scattered): Q15-16 • Chapter 4: Geometry & Trig - Q17-22 • Chapter 5: Statistics - Q23-25 Final footnote: You may notice that a disproportionate number of these problems have you evaluate 3 options (the I, II, III problems). This is because: 1. These problems are harder/longer 2. These problems cover more concepts in less time Just know that on the actual SAT, you won’t be getting nearly as many of these. 1 1 Challenging Functions √ √ 𝑓(𝑥) = 𝑎 𝑥 − 𝑏 + 12 𝑥 − 𝑏 For the function 𝑓, 𝑎 and 𝑏 are constants, and 𝑓(4) = 0. If 𝑓(5) > 0, which of the following could be a value for 𝑎 + 𝑏? A) -20 B) -12 C) -8 D) -4 2 Fraction Algebra 1 - Constant Denominators 16 16 16 = + 𝑎 𝑏 𝑐 Which of the following expresses 𝑎 in terms of 𝑏 and 𝑐? A) 𝑎 = 𝑏+𝑐 𝑏𝑐 B) 𝑎 = 𝑏𝑐 𝑏+𝑐 C) 𝑎 = 𝑏𝑐(𝑏 + 𝑐) D) 𝑎 = 16𝑏𝑐(𝑏 + 𝑐) 2 3 Fraction Algebra 2 - Solving Coefficients 𝑎𝑥3 + 𝑏𝑥2 + 𝑐𝑥 + 𝑑 5 6𝑥 = + 2 (𝑥 − 9)(𝑥 + 2) 𝑥+3 𝑥−3 What is the value of 𝑎 + 𝑏 + 𝑐? 4 Unintuitive Linear Models There are two lawn mowing companies. Company A charges a flat fee of $80 for the first hour, then an hourly rate of $60 for each additional hour. Company B charges no flat fee, but an hourly rate of $75 per hour. After how many minutes will company A’s total cost exceed company B’s? 3 5 Standard Form Solutions 5 𝑥 + 𝑎𝑦 = 𝑏 6 11 𝑥 + 𝑐𝑦 = 2𝑑 10 If the system of equations above has infinite solutions, what must be the value of 𝑑𝑏 ? 6 Percentages 𝑎 is 540% more than 𝑏 and 𝑏 is 0.02% of 𝑐. If 𝑎 is 𝑘% of 𝑐, then what must 𝑘 equal? 4 7 Exponential Functions 1 - Fractional Exponents 2𝑡 𝑓(𝑡) = 𝑎(2) 11 The given function 𝑓(𝑡) models the amount of money in an investment account 𝑡 years after the account is opened, where 𝑎 is a constant. How many months will it take for the initial investment to increase by 700%? 8 Exponential Functions 2 - Constants & Coefficients 𝑓(𝑥) = 𝑘3 (𝑘𝑥 ) + 𝑏 The function 𝑓 is defined by the equation above for 𝑥 ≥ 0. 𝑘 and 𝑏 are positive constants and 𝑘 < 1. Which of the following must be true? I. The maximum value of the function is displayed as a constant or coefficient of the function. II. 𝑓(1) = 𝑓(0) ∗ 𝑘 III. 𝑓(𝑎) < 𝑏 for some 𝑎 > 0. A) I only B) II and III only C) I and III only D) Neither I, II, nor III 5 9 Integer Factors 1 - Maximizing Products 15𝑥18 + 𝑘𝑥9 + 24 The expression above has factors 𝑎𝑥9 + 𝑏 and 𝑐𝑥9 + 𝑑, where 𝑎, 𝑏, 𝑐, and 𝑑 are all integer constants. What is the maximum value of 𝑘? 10 Integer Factors 2 - Identifying Integers (ℎ𝑥 + 𝑘)(𝑞𝑥 + 𝑧) = 𝑎𝑥2 + 𝑏𝑥 + 35 For the expression above, ℎ, 𝑘, 𝑞, and 𝑧 are all integer constants. Which of the following must be an integer? I. 35 𝑘 II. 𝑏 III. − 𝑎𝑞 A) I and II only B) II and III only C) I and III only D) I, II, and III 6 11 Quadratics 1 - Vertex Form 𝑓(𝑥) = −3𝑥2 + 𝑏𝑥 + 𝑐 In the given quadratic function, 𝑏 and 𝑐 are constants. The graph of 𝑦 = 𝑓(𝑥) in the xyplane is a parabola that has a vertex at the point (ℎ, 𝑘), where ℎ and 𝑘 are constants. If 𝑓(−4) = 𝑓(8), and the quadratic function has x-intercepts at (𝑟, 0) and (𝑠, 0), which of the following must be true? I. 𝑟 + 𝑠 = 4 II. 𝑏 < 0 III. 𝑐 < 𝑘 A) I and II only B) II and III only C) I and III only D) I, II, and III 12 Quadratics 2 - Applications A quadratic function models a rock’s height, in feet, above the ground in terms of the time, in seconds, after it’s thrown. The rock was thrown from an initial height of 𝑐 feet above the ground and reached a maximum height of 200 feet above the ground 3 seconds after it was thrown. Then it hit the ground 8 seconds after being thrown. At what initial height 𝑐 was the rock thrown? 7 13 Quadratics 3 - Solutions 2𝑟𝑥2 − 5𝑠𝑥 + 8𝑟 = 0 If the quadratic equation above has one real solution and 𝑟𝑠 = 160, what is |𝑟 + 𝑠|? 14 Polynomial Functions 𝑓(𝑥) = −(𝑥 + 𝑎)2 (𝑥 − 𝑏)(𝑥 − 𝑐) For the polynomial function above, 𝑎, 𝑏, and 𝑐 are positive constants. Let 𝑏 < 𝑘 < 𝑐 for some constant 𝑘. Which of the following must be true? I. 𝑘 > 0 II. 𝑓(𝑘) > 0 III. 𝑓(0) > 0 A) I and II only B) II and III only C) I and III only D) I, II, and III 8 15 Translating English to Math 3 consecutive even integers are ordered from smallest to largest. 5 times the first integer is at least 9 more than the sum of the second and third integers. What is the minimum possible value for the second integer? 16 Unit Conversion If a car accelerates at 108 kilometers per hour squared, what is its acceleration in meters per minute squared? (1 kilometer = 1000 meters) 17 Sine & Cosine In triangle △𝐴𝐵𝐶, the measure of angle 𝐵 is 90∘ , 𝐴𝐵 is a leg with a length of 12, and segment 𝐴𝐶 contains the point 𝐷. Which of the following must be true? 9 I. 𝐵𝐶 = 12 tan(∠𝐶𝐴𝐵) II. cos(∠𝐴𝐵𝐷) − sin(∠𝐷𝐵𝐶) = 0 III. ∠𝐴𝐵𝐷 = ∠𝐵𝐷𝐶 A) I and II only B) II and III only C) I and III only D) I, II, and III 18 Altitudes In triangle △𝐴𝐵𝐶, the measure of angle 𝐵 is 90∘ , and 𝐵𝐷 is an altitude of the triangle. The length of 𝐵𝐶 is 10 and ∠𝐴𝐵𝐷 = 60∘ . What is the length of 𝐴𝐷? 10 19 Arcs & Inscribed Angles 20∘ 𝐴 𝐶 𝐵 If the circumference of the circle above is 90 inches, then what is the length of arc 𝐵𝐶? 20 Circle Formula In the xy-plane, the graph of 𝑥2 + 6𝑥 + 𝑦2 + 2𝑦 = 15 is a circle. Line 𝑘 is tangent to this circle at the point (𝑎, 𝑏), and has a slope of 34 . What is the value of 𝑏? 11 21 Scale Factors Rectangular prism A and rectangular prism B are similar. The height of rectangular prism A is 4 inches and the height of rectangular prism B is 10 inches. If the volume of prism A is 200 cubic inches, then what is the volume of prism B? 22 Pyramids Consider a square right pyramid with a volume of 400 cubic inches and a slant height of 13 inches. The pyramid’s length, width, and height (in inches) are all integers. What is the surface area of the pyramid in cubic inches? 23 Statistics 1 - Integer Mean Data set A consists of 4 integers greater than or equal to 10 but less than or equal to 20. Data set B consists of the same four integers and adds one more integer, which must also 12 be between 10 and 20. What is the largest possible difference between the mean of data set A and the mean of data set B? 24 Statistics 2 - Frequency Chart Analysis Data Frequency 1 2 2 5 3 6 4 5 5 2 The frequency table above summarizes data set A. Data set B is created by multiplying all of the values in data set A by 2. Which of the following must be true? I. The difference between the mean and median of data set B is 0. II. The standard deviation of data set B is equal to the standard deviation of data set A. III. The range of data set B is double the range of data set A. A) I and II only B) II and III only C) I and III only D) I, II, and III 13 25 Margin of Error A sample of students was selected at random from all 11th graders in at a school. Based on the sample, it is estimated that the proportion of 11th graders in at least one AP class is 60% with a margin of error of 5%. Which of the following conclusions are appropriate? I. It is not possible for just 40% of the 11th graders in the school to be in at least one AP class. II. It is plausible that the proportion of all students at the school in at least one AP class is between 45% and 55%. III. If the sample size is increased, the margin of error will drop below 5%. A) I and II only B) II and III only C) III only D) I, II, and III 14 Answer Key 1. D 2. B 3. 72 4. 80 5. 50/33 6. 0.128 7. 198 8. D 9. 361 10. D 11. C 12. 128 13. 26 14. A 15. 8 16. 30 17. A 18. 15 19. 35 20. -5 21. 3125 22. 360 23. 12 24. C 25. C 15