Calculation of Overall Farm Irrigation System Efficiency:

• Water Conveyance Efficiency ($\eta_c$):
  $$\eta_c = \frac{V_f}{V_s} \times 100 = \frac{8,100\text{ m}^3}{9,000\text{ m}^3} \times 100 = 90\%$$
• Water Application Efficiency ($\eta_a$):
  $$\eta_a = 60\% = 0.60$$
• Farm Irrigation System Efficiency ($\eta_s$):
  $$\eta_s = \eta_c \times \eta_a = 0.90 \times 0.60 = 0.54 = 54\%$$
  Alternatively:
  Water stored in root zone = $8,100 \times 0.60 = 4,860\text{ m}^3$
  $$\eta_s = \frac{4,860}{9,000} \times 100 = 54\%$$