For this item, we let x be the amount of the white chocolate in the candy. With this representation and given that there is 3 lbs of peppermint sticks, the total mass of the candy is x+3.
Since white chocolate comprises the 75% of the candy, we make an equation that is,
x / (x + 3) = 0.75
The value of x from the equation is 9 lbs.