In this question, we need to find the total pressure of container D, based on the mixture of the partial pressures of the previous containers, the partial pressures are: A = 1.3 atm, B = 2.16 atm and C = 1.65 atm
Total pressure is defined as the sum of all partial pressures, therefore we will have:
D = A + B + C
D = 1.3 + 2.16 + 1.65
D = 5.11 atm
The total pressure in D will be 5.11 atm