The ratio of girls to boys in liza’s classroom is 5 to 4. how many girls are in her classroom if there is a total of 27 students

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

If you are dealt 4 cards from a shuffled deck of 52? cards, find the probability that all 4 cards are diamondsdiamonds.

Atown has a population of 12000 and grows at 3.5% every year. what will be the population after 7 years, to the nearest whole number?