Asking again: if z varies jointly with x and y, x = 2 and y = 2, z = 7. find z when x = 4 and y = 8.

Which equation matches the graph shown ?

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

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