Determine what is the maximum number of parasites that can feed in the host’s body if the mass of one parasite is 10 g

Determine what is the maximum number of parasites that can feed in the host’s body if the mass of one parasite is 10 g, and 1 g of his body contains 200 kcal of energy. The owner is a herbivore with an average body weight of 40 kg, 1 kg of which contains 2000 kcal of energy. (The process of transformation of energy from one trophic level to another proceeds in accordance with Lindemann’s rule.)

1) Let’s make a diagram of the food chain:
grass -> herbivore -> parasites.
2) Let’s calculate how much energy is contained in the body of one owner:
1 kg contains 2000 kcal 40 kg – x kcal x = 80,000 kcal.
3) Let’s calculate how much energy is contained in the body of one parasite:
1 g contains 200 kcal 10 g – x kcal x = 2000 kcal.
4) According to Lindemann’s rule, parasites will get 10% of the level energy from the herbivorous animal, i.e.
80,000 kcal: 10 = 8,000 kcal.
5) Let’s calculate how many parasites can feed on one host:
8000 kcal: 2000 kcal = 4.
Answer: 4 parasites.