Can anybody with beginner statistics?

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

Which best describes the function on the graph? direct variation; k = −2 direct variation; k = -1/2 inverse variation; k = −2 inverse variation; k = -1/2

Grandpa ernie is shrinking! over the past 4 years his height decreased by a total of 2.4 cm. it decreased by the same amount each year. what was the change in grandpa ernie's height each year