Comparing Population of Adults and Retired Adults

In a certain town, the population consists of 60% adults and 40% children. If the total population is 1,500, how many adults live in this town? Now, let's suppose that 30% of the adults are retired. How many retired adults are there in the town?

Let Quantity A represent the number of adults in the town and Quantity B represent the number of retired adults in the town.