4MA1/2H Jan 2020, Question 25: Sum of an Arithmetic Series
Pearson Edexcel International GCSE Mathematics A 4MA1 · Paper 2H (Higher) · Calculator · 3 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
Mario saves $50 in 2021 and increases his yearly saving by $k up to 2070, totalling $33 125; find k.
Summarised in our own words. Use the official paper for the exact wording and any diagrams.
Solution · 3 marks
- 12021 to 2070 is 50 years: a = 50, n = 50, d = k
- 2Sum = n/2 × (2a + (n − 1)d): 33 125 = 25(100 + 49k)
- 31325 = 100 + 49k, so 49k = 1225
- 4k = 25
Answer25
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 2H January 2020 · 4MA1/2H · 4ma1 jan20 2h · question 25.
Lemmara is an independent study tool, not affiliated with or endorsed by Pearson Edexcel. The worked solutions are Lemmara’s own.