0580/12 Feb/Mar 2025, Question 21: Substitution
Cambridge IGCSE Mathematics 0580 · Paper 12 (Core) · Non-calculator · 4 marks
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The question, in short
Use the formula X = 1/3 w²p: substitute w = 5 and p = 6 to calculate X, then rearrange the formula to express p in terms of X and w.
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Part (a) · 2 marks
Substitute w = 5 and p = 6 into X = 1/3 w²p and work out the value of X.
- 1X = 1/3 × 5² × 6
- 2= 1/3 × 25 × 6
- 3= 50
Answer50
Part (b) · 2 marks
Rearrange X = 1/3 w²p to make p the subject of the formula.
- 1Multiply both sides by 3: 3X = w²p
- 2Divide both sides by w²
- 3p = 3X/w²
Answerp = 3X/w² or p = 3Xw⁻²
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Also searched as: 0580/12/F/M/25 · 0580_m25_qp_12 · 0580 m25 12 · question 21.
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