Atest tube initially holds 25 bacteria. the population of bacteria in the test tube doubles each hour. without making a graph, determine how many hours it will take for the population of bacteria in the test tube to reach 800. explain how you solved this problem.

you > =

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.