The answer is 4,028.0 mm of Hg
It is known that:
1 atm of pressure = 760.0 mm of Hg
Hence:
5.3 atm of pressure = x mm of Hg
Let's use the proportion:
1 atm : 760.0 mm Hg = 5.3 atm : x
After crossing the products:
x = 760.0 mm Hg * 5.3 atm : 1 atm
x = 4,028.0 mm of Hg
Therefore, 4,028.0 mm of Hg are equal to 5.3 atm of pressure