Question

Maize requires 120kg/ha of phosphorus pentoxide (P₂O₅). How much of the compound fertilizer20:20:10 would be applied to 0.4 hectare of land to achieve this rate. (show your working). 

Answer 1

20kg of P₂O₅ is contained in 100kgs of 20,20, 0
Therefore 120kg of P₂O₅ will be contained in (120×100)= 600kg of 20:20:10
                                                                                          20
1 acre of maize requires 600kg of 20:20:10.
Therefore ,(0.4 ×600)= 240kg of 20:20:10