Since 1/3 can't be turned into a decimal, change .5 into 1/2. In order to subtract, the fractions need a common denominator. The least common denominator is 6. So 1/3 turns into 2/6, and 1/2 turns into 3/6. Now you need to take 9 3/6 minus 6 2/6. The answer is 3 1/6 gallons of water.
X = 4 and Y = 9. I did a complicated way of doing it so if u copy it it would look weird
Hope this will help you. It is a little hard to explain.
Supplimentary angles add upto 180 degrees.
Given that angle P is three times angle Q-4 then ;
Let angle P be 3(x-4) = 3x -12
Let angle Q be x
Applying the rule of supplimentary angles;




Divide both sides by 4 to get value of x in degrees

x= 48 degrees
Angle Q = 48 degrees
Angle P = 3x-12 = (3*48)-12 = 132 degrees