Question 1104
 Assume there are x pairs of boots in the inventory.
 Since there are at least ten more pairs of sandals 
 than it has pairs of boots, we have
 number of pair of sandals >= x+10.
 Now there are 28 pairs of sandals = 28, so 28 >= x+10 and we have
 18 >= x.
 Next, we know number of sneakeers (3 times more than x) = 3x + x = 4x,
 Hence  4x <= 4*18 = 72.
 and the greatest possible number of pairs of sneakers in the inventory
 is 72.