Step-by-step explanation:
The cross-price elasticity formula is:
CPE= Δ%q of good A/ Δ%p of good B
The CPE of penguin patties and raskels is:
CPE= -22%/-20%
CPE= 1.1
A positive CPE means that both good are substitutes; often, penguin patties take the place of raskels. An increase in price of penguin patties will affect positively the quantity demanded for raskels.
The CPE of penguin patties and kipples:
CPE= 7%/-20%
CPE=-0.35
A negative CPE means that both goods are complementary, which means that consumers will likely consume them together. An increase in price of penguin patties will affect negatively de quantity demanded for kipples.
Complementary goods should be advertise together because both could be positively benefited by advertising. If the demand for penguin patties increases, it is probable that the demand for patties increases too. If you advertise substitute goods, people will always prefer one, then the advertising will only be effective or for penguin patties or for raskels.