If 3 builders took 5½ hrs to build the wall, 5 builders should take less time, ⅗ of the time=(3/5)(11/2)=33/10=3.3 hrs. Each builder needs to be working 3.3 hrs. So each builder receives £8.90 for each hour or part of an hour. Each gets 3×8.90=£26.70 for 3 hrs work and another £8.90=£35.60 for 0.3hr, the equivalent of 4 hrs work altogether.