Write a direct variation equation for k=10

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

The circumference of a redwood tree trunk is 20π ft, and it is 100 ft tall. what is the approximate volume of the redwood tree trunk? 1,000π ft3 10,000π ft3 4,000π ft3 40,000π ft3

Aramp rises 4 feet over a distance of 10 feet. what is the length of the ramp?