- The weight of a baby mammal is monitored over a 16 -month period.
The weight of the mammal, \(w \mathrm {~kg}\), is given by
$$w = \log _ { a } ( t + 5 ) - \log _ { a } 4 \quad 2 \leqslant t \leqslant 18$$
where \(t\) is the age of the mammal in months and \(a\) is a constant.
Given that the weight of the mammal was 10 kg when \(t = 3\)
- show that \(a = 1.072\) correct to 3 decimal places.
Using \(a = 1.072\)
- find an equation for \(t\) in terms of \(w\)
- find the value of \(t\) when \(w = 15\), giving your answer to 3 significant figures.