Given that:
- price of each clip = ¢ 40
- price of each hairband = ¢ 60
- the average price of (10 clip and band) = ¢ 56


Let the number of clips purchased = c
Number of hairband = 10 - c
Price of total clips = 40 * c = 40c
Price of total hairbands = 60 * (10 - c)= 600 - 60c
$$Average\ price\ =\frac{total\ price\ of\ clip+total\ price\ of\ hairband}{total\ number\ of\ hairband\ and\ clip}$$
$$56=\frac{40c+\left(600-60c\right)}{10}$$
$$560=40c-60c+600$$
$$\frac{560-600}{-20}=\frac{-20c}{-20}$$
$$c=2\ and\ total\ hairbands\ =\ 10-c$$
$$Total\ hairbands\ =\ 10-2=8$$

How many hairbands must be returned for the average price to be ¢ 52?
$$Let\ the\ number\ of\ bands\ to\ be\ returned=b$$
$$\frac{\left(40\cdot2\right)+60\left(8-b\right)}{\left(10-b\right)}=52$$
$$=>\frac{80+480-60b}{\left(10-b\right)}=52$$
$$=>560-60b=52\left(10-b\right)$$
$$=>560-60b=520-52b$$
$$=>560-520=-52b+60b$$
$$=>\frac{40}{8}=\frac{8b}{8}\ \ \ \ \ \ b=5$$
$$5\ bands\ must\ be\ returned\ for\ average\ price\ to\ be\ =\ 52$$
$$Answer\ =\ E$$