Percent problems

The number $\frac{1}{2}+\frac{1}{3}$ is bigger than $\frac{1}{2}-\frac{1}{3}$. Express the difference between these numbers in percents of the smaller quantity.

The pad in the form of (not necessarily regular) octagon is manufactured from a square. The side of the square is $4\mathrm{cm}$. An isosceles right triangle of the hypotenuse $1\mathrm{cm}$ is removed from each corner of the square which results in the desired octagon. How much of the material of the initial square goes to the waste?

Let $a$ and $c$ be positive numbers. A number $b$ equals $96\mathrm{\%}$ of the number $2a+b$ and $64\mathrm{\%}$ of the number $5a+c$. It means that

The initial price of ice bags was $24.20$ zlotys. Now, you can buy $22$ ice bags (which is $10\mathrm{\%}$ more than before) for the same price. What is the percentage decrease in the price of one ice bag?