4MA1/1HR Jun 2025, Question 24: Sum of an Arithmetic Series
Pearson Edexcel International GCSE Mathematics A 4MA1 · Paper 1HR (Higher) · Calculator · 6 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
Arithmetic series starts with (2x + 5), (3y − 4), (4x − 2); first 9 terms sum to 216. Find x and y, showing algebraic working.
Summarised in our own words. Use the official paper for the exact wording and any diagrams.
Solution · 6 marks
- 1Terms equally spaced: 2(3y − 4) = (2x + 5) + (4x − 2), so 6x − 6y = −11
- 22d = (4x − 2) − (2x + 5) = 2x − 7, so d = x − 3.5
- 3S₉ = 9/2 [2(2x + 5) + 8(x − 3.5)] = 216
- 49/2 (12x − 18) = 216, so 12x − 18 = 48
- 5x = 66/12 = 11/2
- 66y = 6x + 11 = 44, so y = 22/3
Answerx = 11/2, y = 22/3
Stuck on a step? Read the free lesson: Sum of an Arithmetic Series
Practise more sum of an arithmetic series questions
Real 4MA1 past-paper questions, marked on your working like the exam, with a worked solution for every part.
Practise free on LemmaraMore past-paper questions on sum of an arithmetic series
Also searched as: 4MA1 1HR June 2025 · 4MA1/1HR · 4ma1 jun25 1hr · question 24.
Lemmara is an independent study tool, not affiliated with or endorsed by Pearson Edexcel. The worked solutions are Lemmara’s own.