0580/31 May/Jun 2025, Question 8: Substitution
Cambridge IGCSE Mathematics 0580 · Paper 31 (Core) · Calculator · 4 marks
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The question, in short
Substitute given values into two formulas and solve for the unknown, finding T when P = 12 and t when W = 369.
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Part (a) · 2 marks
Work out T using T = 3(5P − 8) + 4 with P = 12.
- 1T = 3(5 × 12 − 8) + 4
- 2= 3 × 52 + 4
- 3= 156 + 4 = 160
Answer160
Part (b) · 2 marks
Solve W = 4t + 8 for t given W = 369.
- 1369 = 4t + 8
- 24t = 369 − 8 = 361
- 3t = 361 ÷ 4 = 90.25
Answer90.25
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Also searched as: 0580/31/M/J/25 · 0580_s25_qp_31 · 0580 s25 31 · question 8.
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