Let us first relate to the situation: 3 gallons of paint are used to paint 16 wooden signs.
Thus,we need to solve how much paint did each sign use
Second question: between what two whole numbers does the answer lie?
=> 3 gallons of paints : 16 wooden sign.
=> 3 gallons / 16 wooden signs = 0.19 gallons of paint per wooden sign.
Therefore, every 1 wooden sign we will be suing 0.19 gallons of paint.
Between which 2 whole number the answer lie, well, i can;t really tell since I 'm not sure what you mean.