A lab technician has -gallon of a iodine solution.

Find of amount of iodine solution must be added to make a iodine solution.

Find gallon a iodine solution.

Let is amount of gallon iodine solution.

Make a table:

Content of salt	Amount of iodine	\ Total amount of Iodine \

Observe the table:

Amount of Iodine   plus   Amount of Iodine  equals  Total amount of Iodine.

Solve the equation.

    (Original equation) 

                      (Simplify)

                       (Seperate the like terms)

                                         (Apply additive inverse property: )

                                (Divide each side by )

                                               (Cancel common terms)

Therrefore, gallons of a iodine solution must be added to make a iodine solution.

gallons of a iodine solution must be added to make a iodine solution.