Theory question 105
Farm Surveying and PlanningThe plan shows the survey of a school farm: a trapezium with parallel sides 70 m and 90 m and perpendicular height 45 m.
(a) Calculate the area of the land in hectares
(b) If the school plans to cultivate plantain at a spacing of 4m x 4m on 80% of the land and pineapple at a spacing of 2m x 2.5m on 20% of the land, calculate the number of plantain and pineapple planting materials that would be required for the farm.
Show the model answer
(a) Area = ½ × (70 + 90) × 45 = ½ × 160 × 45 = 3,600 m²; 3,600 ÷ 10,000 = 0.36 hectares
(b) Plantain: 80% of 3,600 = 2,880 m²; area per plant = 4 × 4 = 16 m²; 2,880 ÷ 16 = 180 suckers
Pineapple: 20% of 3,600 = 720 m²; area per plant = 2 × 2.5 = 5 m²; 720 ÷ 5 = 144 suckers/slips
Use the trapezium formula, then divide each area by the space one plant needs.