4024/21 Oct/Nov 2025, Question 21: Changing the subject
Cambridge O Level Mathematics 4024 · Paper 21 (Calculator) · Calculator · 4 marks
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The question, in short
Make a the subject of w = (2a + 5)/(3a − 1).
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Solution · 4 marks
- 1w(3a − 1) = 2a + 5
- 23aw − w = 2a + 5
- 33aw − 2a = w + 5
- 4a(3w − 2) = w + 5
- 5a = (w + 5)/(3w − 2)
Answer(w+5)/(3w−2) or (−w−5)/(2−3w)
Stuck on a step? Read the free lesson: Rearranging Formulas
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Also searched as: 4024/21/O/N/25 · 4024_w25_qp_21 · 4024 w25 21 · question 21.
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