Yes, Applaa is completely free to download and use. There are no subscriptions, no in-app purchases, and no hidden fees. A Pro plan is available for users who want additional AI credits.

What age is Applaa for?

Applaa is designed for kids and young adults aged 7 to 20. The platform scales from beginner drag-and-drop coding to advanced Python, JavaScript, React, and AI/ML.

Is Applaa safe for children?

Yes. Applaa is fully COPPA compliant, shows no advertisements of any kind, uses AI content moderation on all generated content, and provides a parent visibility dashboard so parents can monitor their child's activity.

What can kids build with Applaa?

Kids can build web apps, mobile apps, games, and digital tools using AI assistance. They describe their idea in plain English and Applaa's AI builds working code instantly. Creations can be published to the Applaa Marketplace where kids can earn real money.

What coding languages does Applaa teach?

Applaa's Academy covers Python, JavaScript, React, TypeScript, HTML/CSS, and AI/ML concepts across 130+ free lessons and 150+ challenges.

Does Applaa work on Windows and Mac?

Yes. Applaa is available as a free desktop app for both Windows and macOS. No sign-up is required to get started.

Back to questions directory

A-Level MathematicsYear 2022Q4

12   4. A doctor believes that a four-week exercise programme can reduce the resting heart rate of her patients. She takes a random sample of 7 patients and records their resting heart rate before the exercise programme and again after the exercise programme. Patient A B C D E F G Resting heart rate before 65 68 77 79 80 88 92 Resting heart rate after 63 65 73 76 80 84 80 (a) Using a 5% level of significance, carry out an appropriate test of the doctor’s belief. You should state your hypotheses, test statistic and critical value. (7) (b) State the assumption made about the resting heart rates that was required to carry out the test. (1) ___________________________________________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Turn over 13   Question 4 continued _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________________________________________ (Total for Question 4 is 8 marks)

Paper Source:9fm0-4b-que-20220628.pdf

Get full Socratic AI guidance on this question — free in the Applaa desktop app

Appy Buddy guides you step-by-step toward the answer without giving it away. Type your attempt and get instant, mark-scheme-aware clues that teach you to think like an examiner.

Download Applaa Free →

Applaa Desktop App

Join Applaa Community

Create your own games, learn AI concepts, program interactive apps, and share with a kid-safe community approved by parents. Free forever on Windows and Mac.

Download Free

Available for Windows and macOS · COPPA Compliant

Exam Specification Info

This question is part of the UK A-Level Mathematics syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.

Syllabus levelAdvanced Level (A-Level)

SubjectMathematics

Official MarksVariable (2–6 marks)