Calorific value of cow dung cakes is 7000 J/KG. How much cow dung cakes are required to produce heat energy of 35000 J ?

please answer to this question and its chemistry, COUMBUSTION AND FLAME.

We know that the amount of heat produced by the complete combustion of 1 KG of fuel is called its calorific vallue.It is expressed in "kilojoule per KG(KJ/KG)".

Since, 7000KJ of heat energy is produced in= 1 kg of fuel(cow dung cake)

So, 3500KJ of heat energy is produced in = 35000/7000=5 Kg of fuel(cow dung cakes)

Hope, it'll help you........