TBR Physics :fluids question 7.2 b

[viola101]

a swimmer is at the bottom of a 5 m pool, the gauge pressure is (pgh) 0.5 Patm. if the swimmer rises to the surface, by how much does the total pressure change?

A. the total pressure increases by 33 %
B. the total pressure increases by 66 %
C. the total pressure decreases by 33 %
D. the total pressure decreases by 66 %

How I solved it:

at 5 m below surface
total pressure is Patm + gauge pressure (0.5 Patm)
so that is 1.5 atm

at the surface there is no gauge pressure only the Patm
Pressure final/Pressure initial = 1/1.5 = 0.666, which made me conclude that D is the best answer.

However, the correct answer is C. Can someone please explain this!!!!!!

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[unique135]

At 5m below surface, total pressure = 1.5 atm
At surface, total pressure = 1 atm

Change in total pressure = 0.5 atm (33% decrease)

 

[viola101]

ahhhhh! got confused with the example above it. thanks unique 135!