What is "symbolic representation" in deductive reasoning; and how do you use it to answer a question???

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

Some boys and girls were asked if they had a pet. one third of the group were boys. there were 20 boys. 20% of the girls had a pet. boys with a pet : girls with a pet = 1 : 5 i need to know how many girls there are.

How can you tell when x and y are not directly proportional?