Beverage Dispenser B and Beverage Dispenser C have a total amount of 1014 mℓ of water. For Beverage Dispenser C and Beverage Dispenser D, the total amount of water is 4230 mℓ. The amount of water in Beverage Dispenser B is ³₇ the amount of water in Beverage Dispenser D. What is the average amount of water in the 3 beverage dispensers?
Beverage Dispenser B = 3 u
Beverage Dispenser D = 7 u 

Beverage Dispenser C + Beverage Dispenser B = 1014 --- (1)
Beverage Dispenser C + Beverage Dispenser D = 4230 --- (2)

(2) - (1)
(Beverage Dispenser C + Beverage Dispenser B) - (Beverage Dispenser C + Beverage Dispenser D) = 4230 - 1014
7 u - 3 u = 3216
4 u = 3216

1 u = 3216 ÷ 4 = 804
Beverage Dispenser B = 3 u = 804 x 3 = 2412

Beverage Dispenser B + Beverage Dispenser C + Beverage Dispenser D = 2412 + 4230 = 6642 mℓ

Average amount of water in the 3 beverage dispensers
= 6642 ÷ 3 
= 2214 mℓ

Answer(s): 2214 mℓ