Behold a mixture of oily/hydrophobic (yellow) and water (purplish) molecules. recall that hydrophobic regions are ones with few or no partial charges--so there's nothing for water's hydrogen interaction donors or acceptors to 'play with'. so! how many of the water molecules are 'stuck' contacting at least part of a hydrophobic molecule in this arrangement?
In the attached diagram, there are 5 hydrophobic molecules show, each of which has 9 water molecules shown around it. There are "about 40" water molecules 'stuck' to the hydrophobic molecules.