Home » Maths for Planet Earth » Profiting from Reforestation

Profiting from Reforestation


A small company is planting trees in areas of the Amazon rainforest that have been affected by forest fires.

On any day, the cost to the company, $y, of planting x trees is modelled to be the sum of two elements:

  • a fixed cost
  • a cost that is proportional to the number of trees planted that day

a) Write down a general equation linking y with x for this model.

[2 marks]

The company is subsidised $2 by the government for each tree planted.

On a day when 80,000 trees are planted, the company makes a profit of £500

On a day when 30,000 trees are planted, the company makes a loss of £80

Using the above information,

b) Show that \(y =  0.84x + 428\)

[3 marks]

c) With reference to the model, interpret the significance of the value 0.84 in the equation.

[1 mark]

d) Find the least number of trees that must be planted on any given day for the company to make a profit that day.

[3 marks]

Start exploring

Latest from blog

More Maths for Planet Earth

Carbon capture and storage is method of removing carbon dioxide from the atmosphere and storing it as a liquid underground. Carbon capture and storage
Climate change affects the habitats and environments of many species, some of which won’t be able to adapt fast enough to survive in their
A Level
Since 1800, the number of amphibian species, N, has been decreasing over time, t.  A simple model shows that the rate of decrease of
Jean owns a trucking company (with ten trucks) which produces 1062.8 tonnes of carbon dioxide in the year 2015. The company’s carbon emissions increase