ACT Math free practice questions with answers
Read question 1 and its full worked answer from paper 1 of our 20-paper ACT Math set, then download the 4-page PDF. These are original practice questions, not official past papers. Page updated 3 November 2026.
A right triangle has a hypotenuse of 17 inches and one leg of 8 inches. How long is the other leg, in inches?
A 25
B 9
C 16
D 15
Correct answer: D — 15
- The longest side is the hypotenuse, 17. Use leg² + leg² = hypotenuse².
- 8² + (other leg)² = 17², so (other leg)² = 289 - 64 = 225.
- Other leg = √225 = 15 inches.
- Why the other options are wrong:
- A (25): That adds the sides.
- B (9): You cannot just subtract the sides; use squares.
- C (16): This looks tempting but it does not match the working above. It comes from a small arithmetic or reading slip: redo each step and compare.
Right triangle: a² + b² = c², where c is the longest side; add the squares to find the hypotenuse, subtract to find a leg.
Your sample is downloading. Liked it? ACT Math Paper 1 is the full paper: 45 multiple-choice questions in 50 minutes (calculator allowed), with a worked solution for every question.
Get Paper 1 for A$11.99See all 20 papers from A$11.99More free ACT samples
Questions about this sample
What is in the ACT Math free sample?
The first 3 questions from paper 1 of the set, in the real exam layout, followed by the step-by-step worked answers. It is a 4-page PDF; this page shows question 1 with its answer.
How many full ACT Math papers are there?
20 original papers for students preparing for the ACT. Each is 45 multiple-choice questions in 50 minutes (calculator allowed), with a worked solution for every question. Papers start at A$11.99 and download instantly as a PDF.
Are these official past papers?
No. The sample is taken from our own original practice paper and is not an official past paper or affiliated with any exam authority.