QCEVault

Differential equations and related rates — Question 219

Original QCE Vault practice · 6 marks

Q219 · Practice questionTechnology-freeComplex unfamiliar6 marks

QUESTION 219 (6 marks)

A population satisfies N′=kN(120−N)N'=kN(120-N) with k>0, N(0)=30 and N(4)=60. Time is in days.
a)
Solve the equation to determine k exactly.
[4 marks]
b)
Determine when N first reaches 90.
[2 marks]
Question linkSyllabus coverage

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