0580/21 Oct/Nov 2021, Question 14: Inverse Proportion: y = k/x
Cambridge IGCSE Mathematics 0580 · Paper 21 (Extended) · Calculator · 3 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
y varies inversely with the square root of (x − 2); given x = 4.25 when y = 12, find x when y = 3.
Summarised in our own words. Use the official paper for the exact wording and any diagrams.
Solution · 3 marks
- 1y = k/√(x − 2)
- 212 = k/√(4.25 − 2) = k/1.5, so k = 18
- 33 = 18/√(x − 2), so √(x − 2) = 6
- 4x − 2 = 36
- 5x = 38
Answer38
Stuck on a step? Read the free lesson: Inverse Proportion: y = k/x
Practise more inverse proportion: y = k/x questions
Real 0580 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 inverse proportion: y = k/x
Also searched as: 0580/21/O/N/21 · 0580_w21_qp_21 · 0580 w21 21 · question 14.
Lemmara is an independent study tool, not affiliated with or endorsed by Cambridge International Education. The worked solutions are Lemmara’s own.