How much water should be added to 1 gallon of pure antifreeze to obtain the solution that is 45% antifreeze

Step 1: Let \( x \) be the amount of water to add.

Step 2: The total volume of the solution will be \( 1 + x \) gallons.

Step 3: The concentration of antifreeze in the solution is given by:

\frac{1 \, \text{gallon of antifreeze}}{1 + x} = 0.45

Step 4: Solving for \( x \):

1 = 0.45(1 + x)

1 = 0.45 + 0.45x

1 - 0.45 = 0.45x

0.55 = 0.45x

x = \frac{0.55}{0.45}

x \approx 1.222

Answer: Approximately 1.222 gallons of water should be added.