Question 1067902
a)  There are four 4's and four 8's:
 P{4 or 8} = (4+4)/52 = 8/52 = {{{highlight( 2/13 )}}} 
 
b) There are four of each card rank: 4, 8, and 6:
 P{4, 8, or 6} = (4+4+4)/52 = 12/52 =  {{{highlight( 3/13 )}}}  

c)  There are four 3's and 13 hearts.  However, we are counting 3 of hearts in the four 3's AND again when with the 13 hearts, so subtract one to adjust for this double counting (another way to look at it: there are 12 'other' hearts besides the 3 of hearts):
P{3 or heart} = (4 + 13 - 1)/52 = 16/52  =  {{{highlight( 4/13 )}}}