There is 5000 ml water in a fish tank. then 20% water is evaporated per week. calculate the volume of water left after 4 weeks.
what is the volume of water left?

The answer to your question is: V = 2048 ml

Step-by-step explanation:

Data

Volume = 5000 ml

20% is evaporated per week

Volume of water left after 4 weeks = ?

Process

            1st week               5000 ml    100 %

                                              x                20 %

                                              x = (20x 5000) / 100

                                              x = 1000 ml

After a week there are = 5000 - 1000 = 4000 ml left

            2nd week              4000 ml    100 %

                                                x             20%

                                               x = 800 ml

After two weeks, there are = 4000 - 800 = 3200 ml left

         third weeks              3200 ml    100 %

                                              x            20%

                                             x = 640 ml

After three weeks there are 3200 - 640 = 2560 ml left

         4rd                             2560 ml   100%

                                                x            20%

                                             x = 512 ml

After four weeks there are 2560 - 512 = 2048 ml left

step-by-step explanation:

answer: 12   they all have at least 28 days

step-by-step explanation: haha