The ACT Math Subject Test is a standardized test that measures your mathematical skills and knowledge. The ACT Math test is designed to assess your knowledge of topics, as described in Table 1 and your ability to apply them in problem-solving situations.

Table 1: ACT Math Format

No. of Questions Question Type Time Limit Time/Question
60 Multiple-choice with 4 answer choices 60 Minutes 1 Minute

Table 2: Distribution of question types and skills you can expect to encounter on the ACT Mathematics test

Question Types Subtopics Question Distribution (approx.)
Pre Algebra Basic operations using whole numbers, fractions, decimals, and integers,
Scientific notation,
Square roots,
Ratio, proportion, and percent,
Linear equations,
Ordering numbers by value,
Simple probability,
Simple descriptive statistics,
Data collection, representation, and interpretation,
12-15 questions (20 to 25%)
Elementary Algebra Substitution method for evaluating algebraic expressions,
Expressing functional relationships using variables
Understanding algebraic operations ,
Quadratic equations (with and without factoring)
9-12 questions (15 to 20%)
Intermediate Algebra Quadratic formula,
Absolute value equations,
Inequalities,
Quadratic inequalities,
Rational and radical expressions,
Systems of equations,
Modelling,
Matrices,
Complex numbers.
Polynomial roots
9-12 questions (15 to 20%)
Statistics and Probability Data collection methods 
Probabilities,
Sample space
6-7 questions (8% – 12%)
Coordinate Geometry Slope,
Parallel and perpendicular lines,
Midpoints,
Graphing (in the context of equations and graphs),
Distance,
Conics
9-12 questions (15 to 20%)
Plane Geometry Properties of plane figures,
Properties of circles, triangles, rectangles, trapezoids, and parallelograms Proving basics and techniques,
Volume,
Three-dimensional measurements
12-15 questions (20 to 25%)
Trigonometry Trigonometric identities,
Trigonometric functions (values and properties).
Graphing trigonometric functions.
Modelling using trigonometric functions,
Solving trigonometric equations
3-6 questions (5 to 10%)
Functions Functions (definition, notation, representation, and application),
Linear functions,
Radical functions,
Polynomials,
Logarithmic functions
7-9 questions (12% – 15%)
Integrating essential skills Rates,
Percentages,
Proportional relationships,
Area,
Surface area,
Volume,
Average/median
12-15 questions (20 to 27%)

Here are the ACT formulas students must know before taking the test this fall:

Table 3. Pre-Algebra

Scientific Notation Scientific notation is a way of writing very large or very small numbers using powers of 10.
For example:
The number 3,500,000 can be expressed in scientific notation as 3.5 x 10^6. The number 0.000012 can be expressed in scientific notation as 1.2 x 10^-5.
Square Roots The square root of a product: ?(ab) = ?a × ?b
The square root of a quotient: ?(a/b) = (?a) / (?b)
Ratio, proportion, and percent Direct and Indirect Proportion ( (a1/b1)=(a2/b2) and (a1a2 = b1b2)  
Ratio: The ratio of two quantities a and b can be written as a:b or a/b.    
Linear equations y = mx + b

Table 4. Elementary Algebra

Elementary Algebra   The distributive property: a(b + c) = ab + ac
The commutative property: a + b = b + a, ab = ba
The associative property: (a + b) + c = a + (b + c), (ab)c = a(bc)
The identity property: a + 0 = a, a x 1 = a
The inverse property: a + (-a) = 0, a x 1/a = 1

Table 5. Intermediate Algebra: Linear Equations and Functions

Matrices: Matrix addition and subtraction: A + B = B + A, A – B = A + (-B)
Scalar multiplication: k(A + B) = kA + kB, (k + l)A = kA + lA ·      
Matrix multiplication: AB = C, where C[i,j] = ?k A[i,k]B[k,j]
Complex Numbers: The imaginary unit: i^2 = -1T
he complex conjugate of a+bi is a-bi
Addition and subtraction: (a+bi) + (c+di) = (a+c) + (b+d)i, (a+bi) – (c+di) = (a-c) + (b-d)i
Multiplication: (a+bi)(c+di) = (ac-bd) + (ad+bc)i
Division: (a+bi) / (c+di) = ((ac+bd)/(c^2+d^2)) + ((bc-ad)/(c^2+d^2))i  

Table 6. Statistics and Probability

Mean Sum of the terms / the number of different terms
Average speed Total distance / total time
Probability Probability = Target outcomes / Total outcomes  

Table 7. Coordinate Geometry

Slope Slope = y? – y? /  x? – x?
Slope-Intercept Form y=mx+b
Midpoint Formula (x?+x?) / 2, (y?+y?) / 2
Distance Formula d=?(x? – x?)² + (y? – y?)²
Logarithms Log_b(x.y) = log_bx + log_by
Log_b{x/y} = log_bx – log_by

Table 8. Plane Geometry

Rectangles Area of Rectangle: area = length x width
Perimeter: 2l+2w
Volume: lwh a (h is the height of the figure)
Triangles Area of Triangle: area = (1/2) (base) (height)
Pythagorean Theorem: a2 + b2 = c2
Trapezoids Area: [parallel side a + parallel side b)/2]h
Circles Area of Circle: ? * r²
Circumference = 2? * r
Length of an Arc: (2?r)(degree measure center of arc/360)
Equation of a Circle: (x – h)^2 + (y – k)^2 = r^2 where (h,k) are the center of the circle
Cylinder Volume of a cylinder: ?r2h

Table 9. Trigonometry

SOH CAH TOA sin = opposite/hypotenuse, cos = adjacent/hypotenuse, tan = opposite/adjacent

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