Jack can fill buckets of water four times fast as his sister Jill. They have to fill 400 buckets of water for their village located at the bottom of a hill. Working together, Jack and Jill can complete
the job in six hours.
30. How many hours will it take Jack if he works alone?

Beth divided 9 ounces of her granola recipe into 4 equal-sized amounts. she placed the amounts into individual bowls. the fraction 9/4 represents the number of ounces of granola in each bowl. which other number represents the amount of granola beth has in each bowl? (a) 1 1/4 (b) 2 1/4 (c) 1 3/4 (d) 3 3/4 i need !