If you make $9.50 an hour with 8 hours a day and 40 hours a week you multiply the 9.50 with 40 to get 380. Now, you have the total for one week you can double it to get the pay for two weeks which come out to 760.
We know that the pool drains at a rate of 8 gallons per minute. We can multiply 8*11. 8*11 is 88. We can now subtract 88 from 143. This gives us 55. The swimming pool has 55 gallons of water after 11 minutes.