Can't take the square root of a negative so find a domain where it takes squaer root of 0 wich is allowed hold a sec

there
the denomenator can't be 0 so x cannot be 3, it has to be greater
135 ----- 100%
120 ----- x
------------------------
x = 120*100/135 = 88,8
100-88,8 = 11,2 %
the decrease percent was 11,2 %
hope helped
1.867 is the answer unless you need to round up more.
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