If Abe paints a fence alone, he can complete the task in x hours. If Billy paints the same fence alone, he can complete the task in y hours. If Abe and Billy paint the fence together, they can complete the task in z hours. Complete the equation for z by entering a single fraction in terms of x and y that can be used to find the number of hours it will take Abe and Billy to paint the fence together.

The jones farm has 24 cows that each produce 52 quarts of milk a day. how many quarts are produced each day altogether

Jeffery conducted a survey in his school and found that 30 of the 50 eighth grade students' favorite subject is mathematics. based on the results, jeffery concluded that out of the 200 students in his school, 120 students' favorite subject is mathematics. select the statement that is true about jeffery's conclusion. a. jeffery's conclusion is not valid because the sample was biased since only 200 students were surveyed. b. jeffery's conclusion is valid because the sample was random since all of the students were eighth grade students. c. jeffery's conclusion is valid because the sample was random. d. jeffery's conclusion is not valid because the sample was biased since all of the students were eighth grade students.

Neveah and clint are baking muffins for the bake sale. they need to bake 30 muffins for their display case. clint has baked 4 so far, and neveah has baked 7. how many muffins (m) do they have left to bake? show your work!