You paint 13 1 3 of a wall in 14 1 4 hour. at that rate, how long will it take you to paint one wall?

Find the rate at which you work, that is, the # of walls painted per hour:

13 1/3 walls          40/3

 = wall per hour

14 1/4 hr              57/4

Keep 40/3 as it is; invert the divisor (57/4) and then multiply the result by 40/3:

40        4        160 wall

*  = = approx. 0.94 wall in one hour, or 160/171 wall / hr

  3       57        171 hr

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80